MadaboutKitcars

Decided to dispense with the rear radiator idea today and file it under the 'too difficult' category. The BMW electric pump just wasn't pushing the coolant back round the system so it was actually running hotter with it plumbed in.

Additionally, there would have been a serious ground clearance issue where the hoses ran under the front crossmember, and I couldn't find any other route for them that wouldn't foul something important -



Although I got my engine running I checked the static timing today, which should be 13 degrees btdc. It took a while to check it, I had to stick a piece of white masking tape onto the timing marks to highlight them, and found that it's firing no.1 at about 35 degrees btdc. Hmm, I guess the cam and distributor are in tune with each other, or it wouldn't fire at all, but the crank and cam sprockets are out of sync by a tooth or two. That would also explain the labouring turn over before it fires, the mixture is firing while the piston is still travelling up the bore. Thank goodness I didn't take it for a test drive and rev the nuts off it or I'd be looking at a trail of broken con rods spread up the A10.

Oh well, strip it down and try again tomorrow I suppose.

3rd times the charm T!

Here's a handy link to add to your ponderings about your cooling.
It's the Kenlowe Cooling performance chart that i virtually memorized when sorting out the Countach.

http://www.kenlowe.co.uk/fans/specifiers/fans-cpc.html

You can see the massive differences in CFM (cubic feet per minute) between fan sizes and fan type and then what difference different thickness radiators make.

Personally I found that the Kenlowe fans are considerably more efficient than the cheepos i tried and i ended up with two of their dual-speed (265W) 12" puller fans in the Big Red Car, and TBH i'm tempted to fit one of those in the Miglia just to be on the safe side!

Best of luck sorting it out matey.

Not posted for a couple of weeks as I've had a bit of a nightmare replacing the cam.

I'd never replaced a camshaft before and just assumed that I'd orient it the same way as the old one, line up the timing marks and away we go with more oomph.

What's going to be obvious to anyone that knows about engines is how wrong that simplistic idea was. To cut a long story short, after a week of completely failing to get the engine running properly - it would start but no.1 was firing at about 30 degrees btdc - I put the mk1 cam back in to make sure I hadn't broken something. I even managed to work out how to swap the cam without taking the head off -



Yep, I pulled the cam followers up as far as they'd go with the push rods, then held them in place by tensioning the push rods with elastic bands. Worked a treat when I took out the mk2 cam and put the original back in.

Then I did a bit of research into how I should've timed in the new cam and decided to put it back in using my patented elastic band technique. All went swimmingly until, as I withdrew the mk1 cam, there were three ominous 'clunks', which signalled three of the cam followers falling into the sump.






So, head off followed by an hour spent amusing myself with a fairground style game of 'fish the follower out of the sump through the distributor/cam hole with a magnet taped to the end of a bit of wire so I didn't have to take the engine out and have the sump off.

DON'T USE MY ELASTIC BAND TECHNIQUE, IT'S STUPID.

So, back to timing in the cam. The most intuitively right method I found was this:

With the timing cover off, fit a 360 degree wheel to the end of the crank (I printed one off the 'net, glued it to a bit of cardboard and cut a hole in it so it was a snug fit over the crank pulley) and attach a pointer to a fixed part of the engine or chassis (I used a strip of alloy bolted to one of the radiator mounts).

Find true TDC by sticking something solid through no.1 spark plug hole, then slowly turning the crank one way until it stops, then the other way until it stops, noting the number of degrees on the wheel at each stop. TDC is mid way between them. As it happens, mine was exactly where TDC was marked on the pulley.

Then rotate the crank to the number of degrees corresponding to the mid way point of the cam's inlet timing as follows.

The mk2 Vitesse cam timing is 25-65-65-25, meaning the inlet valves start to open at 25 degrees BTDC and close at 65 degrees ABDC, while the exhaust valves start to open at 65 degrees BBDC, and close at 25 degrees ATDC.

So, by subtracting the number of degrees BTDC that the inlet valve opens from the number of degrees ABDC that it closes, adding 180 and dividing by two, you find the mid point of the inlet valve's duration. In this case that's (65-25+180)/2 = 110 degrees ATDC. Simple, eh?

With the cam chain removed, rotate the crank to the middle of the inlet opening duration AND DON'T MOVE IT AGAIN.

Then rotate the cam until no.1 inlet lobe is on its peak, best checked with a dial gauge -



THEN DON'T MOVE IT AGAIN. I locked the cam in place by refitting the rocker shaft and bolting it down.

Then fit the cam sprocket at whatever orientation the bolt holes will line up with all the slack in the chain on the tensioner side. Turning the sprocket 90 or 180 degrees, or flipping it over and doing the same subtly changes the relationship of the teeth to the chain. Then refit the timing cover and pulley and check that nothing moved when you fitted the sprocket and chain. I did this by ensuring that no.1 inlet rocker was still achieving maximum lift at 110 degrees ATDC, which it was.

So, I now have a running motor again (bit rough as it needs setting up on a dyno), only to be hit by a massive cooling faff which I'll explain in another post in a day or so as this one's gone on for far too long already. Except to post a pic of my car outside Phil J's fab triple garage this afternoon.



Thanks again for the tea and advice Phil.

Makes one realise how clever they were to invent the 'simple' four cylinder engine in the first place, let alone a V8!
Well persevered!

Thought you'd been a bit quiet lately!

You have my sympathies. Its a dreadful feeling being out of your depth! Looks like you have it all sorted now though, well done.

I'm really not into engines like that it terrifies me!


Top marks for effort!

Mister Towed - I'm glad that you finally got your engine sorted out.

And I hope the cooling issue will not keep you off the road.

I've always admired the fact that you have taken on so many of the jobs for your build by yourself.

This really is a hand built car that you can take great pride in your achievements.

Good luck, Paul.

Cooling faff

Thanks for the encouragement guys, there was a point with the cam where I felt I'd bitten off more than I could chew, but with advice from Phil J and a composite of information from two different 'net sites (below) I finally got there.

http://www.tildentechnologies.com/Cams/CamBasics.html

http://www.leicestertr.co.uk/Technical/camtiming.htm

Now to the cooling issue that's been troubling me for quite a while:

When I finished my car last July (can you believe it was a year ago?) the cooling system was specced with a Honda Civic aluminium racing radiator mounted in a home fabricated steel shroud, a 12" electric fan controlled by a thermostat switch in the bottom hose, and a remote filler in the top hose.



This setup worked a treat - at idle the temperature gauge needle stayed bang in the middle of the two dots and when the temperature rose when sitting in traffic after a fast run, the fan would kick in just North of the second dot and bring it back down nicely.

On the way back from Goodwood Revival last September at 70mph on the Motorway though, I noticed that the gauge climbed up to near the red and sat there, taunting me. It didn't actually overheat, but it definitely detracted from the experience of driving it.

Various suggestions were made as to what the problem could be - aluminium rads aren't as thermally efficient as good old copper cored ones; my bonnet scoop could be creating pressure behind the radiator preventing a flow through at speed; my fan shroud could be blocking too much of the core; etc.

Ever since then the problem has remained but the symptoms changed slightly with the gauge climbing especially quickly at lower speeds in traffic after a faster run.

To try to fix this issue I've tried all the following:

I drained, flushed and refilled the cooling system, no difference.

I fitted a bleed valve in the top heater hose, back filled the system from there and bled out any air, no difference.

Having noticed that the fan had stopped cutting in despite the climbing temperature I replaced the thermostatic switch, no difference.

I replaced the head gasket, no difference.

I fitted a secondary radiator at the back with an electric pump to circulate the coolant round it, it actually ran hotter.

I fitted a header tank to feed the top hose and make sure the system was always completely full, no difference.

I cut away all of the unnecessary metal from the fan shroud to let more air flow through the radiator, no difference.

I fitted a 'summer' thermostat, no difference.

I removed the thermostat, no difference.

Then a couple of days ago, as it's never actually overheated, it occurred to me that it could be a gauge problem not a cooling issue, so I took it out on a swift run round the bypass followed by a dawdle back through the Town - the conditions most likely to provoke the gauge to climb into the red, ignoring the gauge as the needle bent against the stop at the red end of the scale.

Luckily, the clouds of steam only appeared as I pulled up on my own drive, not as I tootled past the local High School as thousands of teenagers poured out at closing time. It overheated in dramatic fashion, shooting Icelandic style geysers of steam out from under the bonnet.

I also noted that while steam was gushing out of the overflow and the engine was squealing like a stuck pig, the electric fan remained solemnly still. My multimeter showed voltage at the 'in' terminal of the switch but none at the 'out', while shorting the switch saw the fan kick in as advertised.

Having been sold two defective thermostat switches decided to test them before turning up at the sales counter and loudly proclaiming "I WISH TO REGISTER A COMPLAINT!" So I dropped one into a pan of water and turned the gas up with my multimeter attached and set to resistance. Just as the first vapour began to rise from the surface of the water, 'ping' the multimeter needle shot across the scale as the switch clicked into action just as it's meant to. Hmm.

So, yesterday morning I idled the engine until I could hear steam beginning to make kettle noises inside the engine block, but the fan stayed silent.

I shorted out the fan switch, put my hand behind the fan and found the air that had been drawn through the rad was still cold. Shutting down the boiling engine and opening the drain tap at the bottom of the radiator I found the water that came out was just tepid, in fact, I was actually able to let it run over my fingers without issue.

So I have a circulation problem, not a cooling issue.

I whipped the water pump out and it looks fine (fitted new two years ago) so I rigged up the BMW electric pump I got off ebay to assist with pushing water from the rad back into the engine -



This is wired to come on with the ignition, I've left the thermostat out so there won't be an issue with the water having nowhere to go, and, fingers crossed, seems to have made a difference.

After idling for fifteen minutes with the expansion tank cap off to let any air out I replaced the cap to pressurize the system. After another ten minutes idling the gauge strayed over the second dot but the fan kicked in and brought it back here -



Not out of the woods yet though as I needed to run it in traffic for a while to see what happened, hence the trip over to see Phil yesterday afternoon. The temperature still rose, but only up to about 3/4 of the scale. After Phil had a listen to my motor and suggested advancing the ignition a little (it really needs setting up properly) it ran a little cooler again on the run home and crucially didn't overheat. So, I'm not quite there yet but it looks promising.

As an unexpected bonus I dropped my son off in Town in it yesterday evening and we got caught up in a convoy dropping prom goers off at the local High School. This included many delightful classics; hot rods; rat rod Clampet wagons; Rolls Royces; Ferraris; and farm machinery, although as it's Norfolk the tractors weren't on their way to the prom, just going shopping.

Will post again once I've fully sorted out the cooling issue...

Sorry to hear you've had to go through what i had to go through with sorting out the cooling on the Countach!
But good to hear that you're getting somewhere!

So if fitting the electric pump improved things, for now, are you taking this as a sign that there "has" to be something amis with the mechanical pump? somewhere/somehow?
I mention this as If my old Rover V8 water pump was good enough to pump water through those 2 enormous Renault 5 rads and the miles of plumbing in between, then surely the Triumph pump should be more than up to the job of providing good enough flow rate in your setup?

Fingers crossed that you track down the root cause soon!

Still struggling with cooling somewhat. Fitting the electric pump helped for a while - I took it out for a 20 mile run yesterday and it stayed cool for 15 miles then the temperature rose back up to near the red line again.

With it idling at that the fan kicked in and was pulling hot air out of the rad so at least the coolant was circulating properly. I removed the electric pump again today, refitted the thermostat and went for another long run, getting the same symptoms including the fan kicking in, so the electric pump must've cleared an airlock in the block that was inhibiting proper circulation.

As the radiator still isn't coping with the heat being churned out by the engine
the next step will be to plumb the rear radiator back in, feed it from the heater circuit and boost it with the electric pump. I'll keep the heater control valve in the loop so I can manually include/exclude the rear radiator, while the pump will be triggered by a microswitch on the valve. Hopefully that should help it keep its cool...

On a more satisfying note, the engine had been running rough as hell since I changed the cam and I thought I might have knackered something inside. It was that bad it felt like it was only firing on five cylinders.

I connected my timing light to each lead in turn, and no.6 wasn't firing. That explains why it felt like it was only firing on five, because it was only firing on five.

With the plugs properly gapped and a dicky HT lead replaced I now have my silky six back, but better than ever! It picks up revs noticeably quicker and charges that bit harder into the higher rev range. Nice.

Now looking at a box in the garage with a pair of 1.75 Strombergs with Vitesse adaptors in it. Hmm...

Hi Towed, Glad to hear you've got it running sweetly again.
With regards to the cooling I seem to vaguely seem to remember you had a build up of sludge in the inlet manifold. If that was the case maybe you have a sludge build up in he block which is affecting cooling and reducing the amount of coolant in the system. Might be good to give it a good flush out or even remove some core plugs and have a look.
Just a thought. Good luck.

Cheers Froggyman, I've flushed the system a couple of times and quite a bit of crap came out. The coolant stays pretty clean now where it did go orange with rust as soon as it was put in a year ago.

Still wondering whether the core problem (excuse the pun) is that the aluminium radiator I fitted just isn't as efficient as an old fashioned copper one.

Phil J swears by these, so I might just have to pop across the border into Lincs. and pick one up in a few days -

http://www.ebay.co.uk/itm/FORD-ESCORT-RS2000-MK2-RADIATOR-UPRATED-CORE-42MM-/251442835157?pt=UK_CarsParts_Vehicles_CarParts_SM&hash=item3a8b292ed5

Ultimately it would've been cheaper to buy one of those in the first place than pi$$ about fitting extra radiators.

But if the temp drops when there is airflow through it (i.e. the fans come on) then that can't be the problem, unless there is a ducting/airflow issue when you're on the move and there is not enough air simply passing through it?

"can't" = my best guess and obviously could still be an issue

Hey Mr T, I notice your rad is lower than the thermostat housing, do you have a header tank fitted?

Hey guys, I have a header tank fitted and the fan and radiator can keep the temperature within limits idling from cold, but once you give the motor some exercise it just doesn't cope.

Someone far cleverer than I posted up some info regarding the relative inefficiency of aluminium in conducting heat compared to copper, so I'm going to take the plunge and go back to a traditional, copper cored RS2000 jobbie to see if that solves the issue...

Mr T - Hope the new "old fashioned" radiator is the answer.

Good luck, Paul.

Cooling Six Cylinder

Hello,

Looking forward to your thread(as always!)according your cooling problems.
As I,ve a six cylinder too with coolingproblems.
I,ve used a radiator from a Volvo with header tank and my motor turns so hot it misfires when I have turned it off.
(This can also occur becauseof:no leadfree head,ignition or carb problem)

Does the Escort radiator has the right dimensions to fit your bonnet?

Good Luck

Afternoon T, I know that you have done a lot of research into this but have you seen this thread -

http://www.triumph.org.uk/cgi-bin/forum10/Blah.pl?v-print/m-1210938815/

It covers some of the more Triumph-centric problems rather than the generic. I'm reluctant to offer any suggestions, but the above thread does explore what the air might be doing under the bonnet (the car in question is a Spartan).

You could always get a cheap video device (old phone?), fix it in the engine bay (might need a light source but that is easy) and tape some strands of wool/string to the back of the rad. It might be interesting to see what they are doing at different speeds.

Sorry if I missed this, but have you checked whether coolant will gush out of the drain tap on the block when opened?

Jerome, I measured the space I have between my chassis rails and under the bonnet earlier. From the dimensions the chap who makes them gave me, 20" x 20" (508 x 508mm), including tanks, the RS2000 rad would be too big. Not sure how Phil J got round this unless he had them custom made to a different size, which the chap in Boston will do.

The Honda radiator is 350mm wide x 430mm high x 42mm thick, and I have space for one that's 450mm x 450mm x 42mm, so I've sent those dimensions to the maker to fabricate one for me in copper. I won't need it to have a filler point so I can get away with it being another 20mm taller without sticking out underneath any more than the Honda rad.

Oxford, I'd read that thread (amongst loads of others) whilst trying to fathom what could be wrong. I've convinced myself it's a radiator problem as the coolant system is full, including the block and heater matrix, and now circulates properly, but I'll keep the video-under-the-bonnet idea back for use if the new rad doesn't do the job.

I can't help thinking that you need a better airflow through whatever radiator you have, and to achieve that effectively, you need some way of exiting the hot air from under the bonnet.

Some sort of slits at the rear of the engine end.
I understand you have louvres already, but if they are blanked off they are not effective.

You have a wonderful big air scoop at the front but the hot air obviously rises, and does not have anywhere to go at present.

Having just re-read that thread from the CT, the whole "exhaust gasses into the cooling system" brings back horrible memories!

I know a few Vitesse owners with those Alloy rads fitted who are running fine so I'm looking forward to seeing how this is resolved.
Especially seeing as I have one in a box ready to fit to my Miglia.

I'm having a radiator made by the chap in Boston, and it should be ready for collection tomorrow.

Having spoken to him about the problem - he makes traditional copper cored rads up to four rows thick and also does alloy ones - he confirmed that alloy isn't as efficient at transferring heat from the water to the air as copper. The advantage of using alloy on modern vehicles is that they're much lighter, while modern motors are far more thermally efficient to start with, so they can cope with the demands place on them even though they're not as efficient.

As for the airflow, there's nothing to stop the air coming in at the front from exiting through the front wheelarches. There's a possibility that my main bonnet scoop is creating positive pressure behind the radiator, stopping air from flowing through from the front at speed, but there isn't much room under that scoop for the air to pass down and forwards due to the engine/carbs/airbox being in the way, and once the temperature has risen, slowing down doesn't cool the engine down, which it should if that's the problem.

Should have the new rad plumbed in Friday morning, so will test drive and post results then...

Looking forward to it Towed, really hope it sorts the problem out.

Good luck!

Picked up the new radiator on Thursday, made to measure while I waited.





As you can see, it's a fair bit wider and thicker than the Civic rad, while it's about the same height.

In traditional Sammio building fashion I measured the space available then ordered the radiator 10mm too wide to fit between the chassis rails.

No problem, just needed a bit of clearancing and some new brackets welding on -



Plumbed it all in like so -



Made sure the system was completely full, checked for leaks then went for a blast...

After ten miles of, ahem, enthusiastic driving, the gauge stayed resolutely here -



Success at last! It's running at just under the two dots and when you leave it idling the fan brings it nicely back down after a minute or so.

So, copper 1, aluminium nil, although, to be fair, perhaps the civic rad just wasn't quite big enough.

Well done Mr T!

I bet you are relieved to have sorted it out.