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1979 Triumph Spitfire! - A Goodbye and a Hello


SiC

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1 hour ago, SiC said:

as a DD stamp on the red rotor arm. But it's an accuspark distributor and DD doesn't supply to them. So it's a fake DD.

I've been buying direct from Martin. Or from the club  who obvs also buy direct. Hopefully weeds out the chance of knock offs 

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2 hours ago, Joey spud said:

It's a shame you didn't check and see if you had lost a spark from the coil lead and/or a plug lead while it was in no go mode.

Problem is that in no go mode I used the starter and then pushed to get out the way. Tried to start again and nothing. 

Popped the bonnet, dizzy cap off and heatsinked the accuspark module with my hand. Dizzy cap on then started again. Ran perfectly!

So either it's the module or the act of removing the cap that sorted it. 

Literally just run it up again and it's currently idling like a dream. 

I might run some heat over the module and try again. 

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1 hour ago, Matty said:

I've been buying direct from Martin. Or from the club  who obvs also buy direct. Hopefully weeds out the chance of knock offs 

I'm lucky in that I have a Moss branch in town. I'd be highly surprised if Moss sell knock-offs, especially for how much they charge!

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@Joey spud... "A favorite get you home fix if you had lost feed to a coil or fuel pump was to unplug the dead wire and run a wire from a headlamp instead so lamp on engine runs,lamp off engine stops obviously can't do that nowadays."

Cool.... I'm doing exactly that to control my DRLs. Taking power from the dash lights [SuziQ has earth switching so very messy taking a direct on/off to the relay] 👍

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I spent an age with a heat gun trying to see if the module would fail when hot. Measured surface temperature reached 80c, so plenty hot enough. Still ran fine. There was some mention that the coil might be an issue, so I tried heating that up too. Again no issues.

Timing gun showed it bang on 10 degrees at idle. Perfectly where it should be.
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Inside looked fine. It was a bit oily though. Not that I expect that to cause any enormous issues. Certainly not the amount I found. This was from the oiler pad under the rotor arm where someone was a bit too generous with the oil.
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I dug out my spare 123 Ignition as I was going to put it on anyway. Static timed it and checked the dynamic again. All perfectly fine. The timing was wandering a fair bit but I think the chain tensioner goes a bit slack when hot.

Used new ignition leads but had to reuse the king lead as the new set didn't fit on this coil. It's a 1.6 ohm "sports" coil so not sure if they deliberately have a different terminal that is fatter? Or just accuspark doing this so you have to buy their leads.
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Also fitted a Ctek charge cable in the expectation of putting it into storage. I usually prefer the fused version but I didn't have any left. I don't have much luck with any battery clamp isolators as I find they end up breaking after a while. But I may see if I can get another for this so I can shut the power off completely when put away out of season.
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Then stashed it away in storage for now. It stops the elements getting into it until the Dolomite is put here the week after next and I have garage space again.

Drive went perfect. I don't know if it's butt dyno at play but it feels more sprightly. Could also be a better advance curve match for the engine than the generic accuspark one (which probably varies a lot between units).
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I've ordered an original Lucas distributor too. I may keep this in the boot as a setup and drop in emergency spare. Something I do with the MGB. I already have the old accuspark unit, HT leads, spare coil and jumper cable in the boot as an emergency get home setup. The lack of points in the 123 does make it a lot less faff though. No gap or dwell time to worry about with it closing up as the points wear.
It's still tempting to give it a try though as it should be a good match for the engine.
https://www.ebay.co.uk/itm/164844912424


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Hmm! That's something I hadn't considered.

If it was fuel related, would a misfire be expected? I guess possibly if it was running lean but I'd have thought the damper pistons would stick if shite has got through that far. 

The needle valves definitely weren't stuck open as they didn't overflow. They could have got blocked on the inlet but then it's not happened since so I'd thought it would have been small enough to pass through. 

There is also the possibility of a bad seal in the pipework that is allowing air through. But it played up when idling and fuel flow is low. So I'd have thought the float bowls should have been relatively full. This is where a clicky SU pump is useful as you can quickly gauge the attempted fuel flow rate by how much noise it's making. 

When I restarted it this morning, I didn't do anything different from when it broke down last night. I ran it for a good hour or so on the drive in the exact same setup. Absolutely fine. When it broke down I tried a few times to restart and then drove it along on the starter. It did cough a bit on the starter so it was trying. The only thing I did last night before it restarted fine was take the cap off and hold onto the accuspark module. I didn't touch any of the fuel lines or carbs. 

My gut feel on intermittent faults and sudden breakdowns is that it's an electrical problem. 

I wish I could have done some more diagnostics when it broke. But I wanted to get it back home again and I find always looks better/improve confidence if you get the car running again - especially with the other half sitting there. I'd probably have done more diagnostics if taking the cap off/holding the module didn't fix it. As it started working again, the next key objective was to get it home high and dry.

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1 hour ago, N Dentressangle said:

When I've been working on a car and it throws a fault shortly afterwards I usually suspect the last thing I disturbed.

9 times out of ten tbf. Makes sense when you think about it, not least as the most obvious place to start, rather than rushing off half cocked.  What's next for you anyhow, now si has got this?

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11 hours ago, Matty said:

9 times out of ten tbf. Makes sense when you think about it, not least as the most obvious place to start, rather than rushing off half cocked.  What's next for you anyhow, now si has got this?

This:

MvNIXeE.jpg

Inherited from the house in Manc you met me at. Not remotely worthy of a thread, I'm hoping 😉

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12 hours ago, SiC said:

Hmm! That's something I hadn't considered.

If it was fuel related, would a misfire be expected? I guess possibly if it was running lean but I'd have thought the damper pistons would stick if shite has got through that far. 

The needle valves definitely weren't stuck open as they didn't overflow. They could have got blocked on the inlet but then it's not happened since so I'd thought it would have been small enough to pass through. 

You could get a piece of dirt stuck in the needle valve preventing it from opening fully, or perhaps in the jet itself which only cleared with throttle.

Stopping would allow the float bowl to refill.

It's a possibility. See if it recurs and go from there I guess?

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I've been having a think about this and what could have caused the FTP. It can only be speculation as I don't have any hard facts to prove the root cause. I would like to know what it is though, so I can prevent it happening again.

As some might be aware, I don't trust accuspark modules. What that has done though I think is give me confirmation bias. I have no evidence to prove the module is at fault. Neither the distributor timing. So I really can't blame those parts.

Based on what happened when driving, I don't think it's fuel related either as the misfire was intermittent and light. I'd have expected a low/empty float bowl to be running really rough. I might try pinching the line with my fuel clamps to see what it's like. Certainly if I lift a damper piston at idle, it'll cause the engine to cut out.
If one carb is lean and two cylinders are nearly down (i.e. when I've been tuning a carb), I find a 4cyl really does not want to idle at all. This idled but stumbled when in the Tesco car park.

So what could it be?

There's a bit more data and something I think I overlooked, possibly dismissing too readily...


Inside looked fine. It was a bit oily though. Not that I expect that to cause any enormous issues. Certainly not the amount I found. This was from the oiler pad under the rotor arm where someone was a bit too generous with the oil.
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Notice how the rotor arm is shiny? That's because I took it off and cleaned it up before the eventful trip. I didn't mention it in my post before when I did the bits as it was even less exciting than the rest of the content.

Going back to that quote where I say about the cap being oily? Under the rotor arm is an oily pad. This was very wet. I also don't remember the cap being oily inside when I had it off. There are no photos before unfortunately so I can't say for sure.

When I put the rotor arm back on, I'm wondering if that excess oil may have squished out. Or at the very least disturbing the felt pad led to some of the oil getting out.

Then driving caused that oil to be flung all around the distributor cap. Made worse by the top half of the lobe section being snapped back and forth from the weights reacting to engine revs.

This is a high res image of the cap. Note the HT Posts. It doesn't come out in the photo that well but there a thin film of oil all around inside it.
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Zooming in, those HT posts look rather golden in parts. Possibly oil from being flung on there and creating an insulation that stopped it running? Maybe the oil ran down from the top of the cap when it was warm and at lower revs with less to blow it up, caused it to run down easier and create a spot where it prevented a cylinder firing?

Removing the cap could have moved any oily residue that was insulating the spark. Then allowing it to run again.

What do we think? Plausible?
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4 minutes ago, SiC said:

I've been having a think about this and what could have caused the FTP. It can only be speculation as I don't have any hard facts to prove the root cause. I would like to know what it is though, so I can prevent it happening again.

As some might be aware, I don't trust accuspark modules. What that has done though I think is give me confirmation bias. I have no evidence to prove the module is at fault. Neither the distributor timing. So I really can't blame those parts.

Based on what happened when driving, I don't think it's fuel related either as the misfire was intermittent and light. I'd have expected a low/empty float bowl to be running really rough. I might try pinching the line with my fuel clamps to see what it's like. Certainly if I lift a damper piston at idle, it'll cause the engine to cut out.
If one carb is lean and two cylinders are nearly down (i.e. when I've been tuning a carb), I find a 4cyl really does not want to idle at all. This idled but stumbled when in the Tesco car park.

So what could it be?

There's a bit more data and something I think I overlooked, possibly dismissing too readily...
 

 


Notice how the rotor arm is shiny? That's because I took it off and cleaned it up before the eventful trip. I didn't mention it in my post before when I did the bits as it was even less exciting than the rest of the content.

Going back to that quote where I say about the cap being oily? Under the rotor arm is an oily pad. This was very wet. I also don't remember the cap being oily inside when I had it off. There are no photos before unfortunately so I can't say for sure.

When I put the rotor arm back on, I'm wondering if that excess oil may have squished out. Or at the very least disturbing the felt pad led to some of the oil getting out.

Then driving caused that oil to be flung all around the distributor cap. Made worse by the top half of the lobe section being snapped back and forth from the weights reacting to engine revs.

This is a high res image of the cap. Note the HT Posts. It doesn't come out in the photo that well but there a thin film of oil all around inside it.
5d3a924752bea0651869558a582a14e5.jpg

Zooming in, those HT posts look rather golden in parts. Possibly oil from being flung on there and creating an insulation that stopped it running? Maybe the oil ran down from the top of the cap when it was warm and at lower revs with less to blow it up, caused it to run down easier and create a spot where it prevented a cylinder firing?

Removing the cap could have moved any oily residue that was insulating the spark. Then allowing it to run again.

What do we think? Plausible?

 

Plausible reason

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22 minutes ago, N Dentressangle said:

Never did anything like that to me, even in heavy town traffic with plenty of heat, but you never know.

That's why I've dismissed the carb over heating or the fuel vapourising as I would have thought you'd seen that. Plus I had it idling on my drive for a good half hour, maybe even an hour yesterday. 

I do think I'll need to put the mechanical fan on before we get to summer weather finally. I did notice that the gap between the electric fan and radiator stops a lot of the air flowing through. So it ends up blowing over the top of the radiator. Possibly less of an issue with the bonnet shut but that fan is also on the wrong side for the manifolds & carb. Where as the mechanical fan would be sucking air through the radiator directly onto the carbs. 

I can't see any easy way of mounting the electric fan much closer or even directly on the radiator. 

PXL_20230514_133817134.thumb.jpg.b19dc709d1a637cf2c16c0fef0197977.jpg

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I will also say that it hasn't dented my enthusiasm with the car. I'm already quite missing it and wish I could have gone out for a spin in it this evening.

For any one reading and to make clear, I fully expected to have a few teething issues on any car I buy, not least a late 70s BL product! It's one of those things that when any car changes owner, they do have a habit of breaking. Possibly because it's the different way people drive. 

Mrs SiC did ask me the other day if my classics break because I drive them too hard and I was really supposed to rev and chuck them around like I do. I said yes as they're sports cars after all! 🤣

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14 hours ago, SiC said:

I've been having a think about this and what could have caused the FTP. It can only be speculation as I don't have any hard facts to prove the root cause. I would like to know what it is though, so I can prevent it happening again.

As some might be aware, I don't trust accuspark modules. What that has done though I think is give me confirmation bias. I have no evidence to prove the module is at fault. Neither the distributor timing. So I really can't blame those parts.

Based on what happened when driving, I don't think it's fuel related either as the misfire was intermittent and light. I'd have expected a low/empty float bowl to be running really rough. I might try pinching the line with my fuel clamps to see what it's like. Certainly if I lift a damper piston at idle, it'll cause the engine to cut out.
If one carb is lean and two cylinders are nearly down (i.e. when I've been tuning a carb), I find a 4cyl really does not want to idle at all. This idled but stumbled when in the Tesco car park.

So what could it be?

There's a bit more data and something I think I overlooked, possibly dismissing too readily...
 

 


Notice how the rotor arm is shiny? That's because I took it off and cleaned it up before the eventful trip. I didn't mention it in my post before when I did the bits as it was even less exciting than the rest of the content.

Going back to that quote where I say about the cap being oily? Under the rotor arm is an oily pad. This was very wet. I also don't remember the cap being oily inside when I had it off. There are no photos before unfortunately so I can't say for sure.

When I put the rotor arm back on, I'm wondering if that excess oil may have squished out. Or at the very least disturbing the felt pad led to some of the oil getting out.

Then driving caused that oil to be flung all around the distributor cap. Made worse by the top half of the lobe section being snapped back and forth from the weights reacting to engine revs.

This is a high res image of the cap. Note the HT Posts. It doesn't come out in the photo that well but there a thin film of oil all around inside it.
5d3a924752bea0651869558a582a14e5.jpg

Zooming in, those HT posts look rather golden in parts. Possibly oil from being flung on there and creating an insulation that stopped it running? Maybe the oil ran down from the top of the cap when it was warm and at lower revs with less to blow it up, caused it to run down easier and create a spot where it prevented a cylinder firing?

Removing the cap could have moved any oily residue that was insulating the spark. Then allowing it to run again.

What do we think? Plausible?

 

I've over oiled the pad before and caused an intermittent miss fire. I think. Me being me I then changed the consensor and the problem went away so I'll never know which was the problem. Just give everything a good clean up and run it. If you haven't changed anything else and the problem doesn't reoccur then your diagnosis was right.

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13 hours ago, SiC said:

I will also say that it hasn't dented my enthusiasm with the car. I'm already quite missing it and wish I could have gone out for a spin in it this evening.

For any one reading and to make clear, I fully expected to have a few teething issues on any car I buy, not least a late 70s BL product! It's one of those things that when any car changes owner, they do have a habit of breaking. Possibly because it's the different way people drive. 

Mrs SiC did ask me the other day if my classics break because I drive them too hard and I was really supposed to rev and chuck them around like I do. I said yes as they're sports cars after all! 🤣

No worries. I think you probably drive a fair bit harder than me, which is great - as you say, it's what these cars were built for and I certainly drove them that way 30 years ago!

Plus you'd be disappointed if there were nothing to fix 😉

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We went to a local car show today with my father in law. Car got us there and back just fine. Had a few things that I'll mention in a bit.

I have to say I do like these Z4. If I get bored of my Boxster, maybe I would change to one of these.
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318Si looked smart. Good to see a small engined BMW getting some love.
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Fez 328 was a nice example.
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This less so, with filler falling off around previous repairs. Shiny though so the owner must love it.
Kinda how I need to get my Dolomite.
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This MK1 was in much better condition. I'd be tempted with one of these one day. I think they're pretty cool.
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Golf GTi is a cool car. Wouldn't pay what they go for though.
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Old fast Ford. Yawn.
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I do like a good Capri though. This was a minter.
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Some other old Fords
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This was absolutely mint Mini. Not sure I've seen one this immaculate for a long time.
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Old Bristol with Midget indicators
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Then everything else
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The owner of this was trying to tell me that old Impreza are bargains for that they are. £15k buys you a nice one apparently.
While cool, there are many other cars I'd buy for that instead of an Impreza.
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While leaving, I noticed this on the boot lid of my car.
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So issues.

It didn't cut out so that's a good start!

Clutch started juddering badly on the way back. Not sure if it's because it's hot or something else. Previous owner to ND put a new clutch in it looking at the history. Modern Bork and Beck are not great quality. I think that's about all you can get now.
It's likely I'll need to pull the box and engine at some point. The Speedo is very annoying and nearly came a cropper when I passed the old biddy speed patrol on the way to the meet. Thankfully I had my phone up with GPS speed, so I could bring my speed down a bit.

The biggest issue is heat and cooling.
It's temperature is getting pretty spicy under the bonnet on a run. It got higher than this and on the last peg before the H.
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The fan switch is becoming even more temperamental. It didn't work at all earlier even after turning it back and forth. I was about to pull the connector off and it kicked in again. However I didn't trust it so I connected it permanently on for now with the extra spade terminal I crimped on to allow it to be overridden. I noticed the fan running quicker on this terminal which suggests that the switch terminals are high resistance.

Looking at the wiring, there is a relay to turn the fan circuit on with the ignition. I was expecting the thermostat switch to go through this too but instead it directly switches the fan motor. The motor draws just over 16a peak starting up and falls back to around 11a running.
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According to the rating (this is off an eBay listing of an identical switch) it should be 16A but the different spec on the paper label doesn't inspire confidence. It's also the AC rating which is often higher than a DC rating.
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There is a large gap between the fan and the radiator. This is really not helping things as most of the air goes over the surface of the rad rather than through it. I can't see how I can get the fan much closer and I don't want it touching the rad as it might damage it.
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I think I'll have to figure how to get the mechanical fan attached. It's the best solution really. Even though the carbs are behind a heatshield, the float chambers are almost too hot to touch. This can't be helping with fuel vapourising. You get a whiff of petrol now and again, especially if starting off, so I suspect the heat isn't doing them good.

I might go for a fiddle in a minute while the weather is nice.

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Si, the firm @Mallyrecommended did a lovely job on my speedo. Pretty accurate as well compared to GPS. They do repairs via post or courier. 

Edit

Now I've repaired the fault, my electric fan set up is very effective. Mines at the rear of the rad and drawing through. Twin fans and it has a hell of a draught on it. Is it possible to move the rad forward and squeeze a set up behind?

Edit edit

Like this

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3 hours ago, Matty said:

Si, the firm @Mallyrecommended did a lovely job on my speedo. Pretty accurate as well compared to GPS. They do repairs via post or courier. 

It is an option but I want to make sure I'm not side stepping any other issue. Such as the wrong Speedo drive in the overdrive. They'd have to re-gear the speedo if that's an incorrect one. On the Triumphs of this age they seem to have all 1000TPM and correct it in the box. The TPM would need to go down (I think!) to fix this issue. Not sure how much but presumably 10% if that's the error. Again if I get the actual teeth count in the overdrive, the correction needed to be applied can be. 

3 hours ago, Matty said:

Now I've repaired the fault, my electric fan set up is very effective. Mines at the rear of the rad and drawing through. Twin fans and it has a hell of a draught on it. Is it possible to move the rad forward and squeeze a set up behind?

There should be room for a mechanical fan. That's how God Triumph intended and should be all that is needed. I have a correct fan but I need to find some correct bolts and it needs to be fitted. Both I've not done yet. 

With the fan on permanently with the ignition, I've just been out with Mrs SiC to the beach and back with it absolutely fine. Temperature stayed bang on where it should be. 

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2 minutes ago, SiC said:

an option but I want to make sure I'm not side stepping any other issue. Such as the wrong Speedo drive in the overdrive. They'd have to re-gear the speedo if that's an incorrect one. On the Triumphs of this age they seem to have all 1000TPM and correct it in the box. The TPM would need to go down (I think!) to fix this issue. Not sure how much but presumably 10% if that's the error. Again if I get the actual teeth count in the overdrive, the correction needed to be applied can be.

You see that's your problem. You will insist on doing the job properly 😄

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With the weather starting to get hotter, the cooling situation really needs to be sorted.

So dug out an old BL fan
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Cleaned off the oily filth
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Dug out my box of bolts
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Fitted it
This took far longer than it should due to limited access. My flexi stubby ratchet spanners came in very handy.
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It required a bit of mold grip reshaping of the guard by the radiator cap as it caught the fan
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Then ran it up to make sure it didn't hit still when up to speed
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This is the front shot of the radiator. The electric fan is more on the other side. While I probably could get it moved across, I'm quite happy it here as it doesn't obstruct the mechanical fan I've just fitted.

I'll still wire the electric fan into a switch. While it should never be needed, it may come in handy on a really hot day. After all it's going to be a spring/summer car for me and that'll likely mean it'll be used in very hot days. I don't want that gauge creeping up in stationary city traffic where the mechanical fan isn't doing much, with no means of resolving it.
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While I was putting the roof up in the dark, I noticed my light on the bonnet shining through some holes in the footwell area. Presumably this is why they got so soaking wet the other day. Water drains on top of the scuttle area and must leak through these holes.
I'll find a way of plugging them perhaps.
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Hopefully this fan will be the end of any cooling issues and that gauge will stay fixed in the normal end. My experience on heatsinking is that even a small bit of airflow makes an enormous difference over no airflow.

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@SiCI love the way some fans have irregular blade spacing,  presumably to prevent acoustic beats/resonances.  It's difficult to judge the clearance between fan and rad on the photo.  Are you confident that the engine won't swing from torque effects when under load and/or jiggle on rough surfaces and clout the rad?  I don't know whether a Spitfire engine has stiff mountings or even how many it has.  I suppose that with the transmission going to a chassis mounted diff, one would expect engine movement to be axial with no longitudinal movement, so it should not be a problem.  Many years ago I had radiator cloutage by the fan in a Reliant (not the one I still own). It was then that I discovered the need to grease the sliding joint in the prop shaft.  Not a problem with your independent rear end.  

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8 hours ago, RayMK said:

you confident that the engine won't swing from torque effects when under load and/or jiggle on rough surfaces and clout the rad?

Certainly not confident! Even though it's an aftermarket radiator, it lines up all with the existing factory mounts and I believe is a correct one for a Spitfire. However there is no guarantee that things won't shift. I'll have a measure. 

There is enough gap to get a 3/4inch bolt into the fan and a spanner. Not enough for a standard socket and ratchet. So I'd guess at least 3/4inch of clearance, maybe 1 inch. 

Not a huge amount of room but it's not butted directly up to the rad. 

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On 5/15/2023 at 10:38 PM, SiC said:

That's why I've dismissed the carb over heating or the fuel vapourising as I would have thought you'd seen that. Plus I had it idling on my drive for a good half hour, maybe even an hour yesterday. 

I do think I'll need to put the mechanical fan on before we get to summer weather finally. I did notice that the gap between the electric fan and radiator stops a lot of the air flowing through. So it ends up blowing over the top of the radiator. Possibly less of an issue with the bonnet shut but that fan is also on the wrong side for the manifolds & carb. Where as the mechanical fan would be sucking air through the radiator directly onto the carbs. 

I can't see any easy way of mounting the electric fan much closer or even directly on the radiator. 

PXL_20230514_133817134.thumb.jpg.b19dc709d1a637cf2c16c0fef0197977.jpg

That fan should be in direct contact with the rad. Most aftermarket kits have little fasteners that you push through the gaps in the fins. Sucking eggs comment…. It is rotating in the correct direction….?

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