Engine back in but now running hot

[dannyboy]

Why do these things always happen a few days before a family holiday?!

So ... I thought I'd successfully dropped the engine out of my 72 crossover, repaired leaky petrol tank breathers and replaced the engine but unfortunately my dipstick temp gauge now reads a pretty constant 110-120 deg C, whereas before it was around 90.

Engine running just fine - power as before, if anything a little smoother and enough grunt to top 70mph two-up which seems OK.

Can't think what I've messed up but here's a little list of jobs that got done at the same time. Hopefully I've cocked up something obvious as I don't think I've time to take the engine out again.
1. petrol tank breathers connected up to oil bath air filter whereas previously they vented into engine bay... Could this be making it slightly richer? Surely marginal...
2. engine oil/strainer/gaskets replaced - 20W50 oil as before
3. rocker covers changed from SCAT to stock along with new gaskets in an attempt to solve leaks
4. valve clearances all adjusted back to 6 thou - a couple were on the tight side. Just possible I've erred on the side of caution here.
5. new foam seal round tinware
6. one new aluminium air hose as I tore one taking it off
7. new pertronix igniter as I managed to fry the old one (yes, it's true, they burn out instantly if you connect them up the wrong way round). Hmmm, wonder if I need to reset the timing even if all I did was drop a new pickup in the dizzy in the same mounting? But if the timing was wrong the bus wouldn't be pulling right, like it is, would it?
8. installed split charge relay and leisure battery
9. put some sound proofing above the engine and in front of the petrol tank

Was really hoping to get the family + camping gear to North Devon on Friday but unless I can solve this pronto I'm going to have to cave in and go in the Volvo + trailer

So, come on, what have I missed?!!! And no, I can't see any bits of tinware lying around that I've forgotten to replace! (Although I have to admit I may be going crazy and imagining it was complete when I'm sure it wasn't quite...)

Another question: should I notice poorer performance as it's running hotter? Could it just be the temp sender's changed?

Things I suppose I'll try tomorrow:
1. remove petrol breather from air intake
2. check the foam seal again...
3. check the temp sender is working properly with a kettle
4. pray harder

Dan

 

[lard]

Why do these things always happen a few days before a family holiday?!

So ... I thought I'd successfully dropped the engine out of my 72 crossover, repaired leaky petrol tank breathers and replaced the engine but unfortunately my dipstick temp gauge now reads a pretty constant 110-120 deg C, whereas before it was around 90.

Engine running just fine - power as before, if anything a little smoother and enough grunt to top 70mph two-up which seems OK.

Can't think what I've messed up but here's a little list of jobs that got done at the same time. Hopefully I've cocked up something obvious as I don't think I've time to take the engine out again.
1. petrol tank breathers connected up to oil bath air filter whereas previously they vented into engine bay... Could this be making it slightly richer? Surely marginal...
2. engine oil/strainer/gaskets replaced - 20W50 oil as before
3. rocker covers changed from SCAT to stock along with new gaskets in an attempt to solve leaks
4. valve clearances all adjusted back to 6 thou - a couple were on the tight side. Just possible I've erred on the side of caution here.
5. new foam seal round tinware
6. one new aluminium air hose as I tore one taking it off
7. new pertronix igniter as I managed to fry the old one (yes, it's true, they burn out instantly if you connect them up the wrong way round). Hmmm, wonder if I need to reset the timing even if all I did was drop a new pickup in the dizzy in the same mounting? But if the timing was wrong the bus wouldn't be pulling right, like it is, would it?
8. installed split charge relay and leisure battery
9. put some sound proofing above the engine and in front of the petrol tank

Was really hoping to get the family + camping gear to North Devon on Friday but unless I can solve this pronto I'm going to have to cave in and go in the Volvo + trailer

So, come on, what have I missed?!!! And no, I can't see any bits of tinware lying around that I've forgotten to replace! (Although I have to admit I may be going crazy and imagining it was complete when I'm sure it wasn't quite...)

Another question: should I notice poorer performance as it's running hotter? Could it just be the temp sender's changed?

Things I suppose I'll try tomorrow:
1. remove petrol breather from air intake
2. check the foam seal again...
3. check the temp sender is working properly with a kettle
4. pray harder

Dan

I've just replaced my engine - I also wired the ignition the wrong way round (put the black lead from the loom on the negative terminal :roll: and fried it :shock:

good to know that I'm not the only one :mrgreen: - Can't help on the temp change, though I haven't got a temp sensor so haven't a clue what it was/is now and maybe that's a blessing - did you check the thermostat and flap movement after you re-installed the engine? Made sure you put the heat exchanger connections back on? the pieces of tin underneath the pushrod tubes on each side?

Can't help checking the timing again - though it should be exactly the same?

 

[dannyboy]

Hi Lard - thanks for your help.

I've just replaced my engine - I also wired the ignition the wrong way round (put the black lead from the loom on the negative terminal :roll: and fried it :shock:

Exactly what I did. One of those things you do once and once only.

did you check the thermostat and flap movement after you re-installed the engine?

Well, now you mention it, no I didn't. And guess what: on closer inspection I find that there is no thermostat, nor bracket, nor rod. This is what greets me having removed that bottom bit of tin:
[photobucket]http://i1111.photobucket.com/albums/h473/dsladden/photo.jpg[/photobucket]

Made sure you put the heat exchanger connections back on?

yup

the pieces of tin underneath the pushrod tubes on each side?

yup

Now then, can I check all my flaps are at least open without removing the engine? Is it possible they got inadvertantly closed when the engine was out?

Cheers
Dan

 

[uber cool]

If it was my engine and I had changed the point or anything on the dizzy I'd always re check the timing. Do you have vac advance? Is that connected and working properly?
The first things I'd check for running hot are

Is the temp gauge working properly?
Is the timing correct? Test it dynamic or over 3000 rpm with a strobe lamp
Is the mixture correct, lean will run hot?
Is valve gaps correct?
Check there is no tin ware missing or badly fitted?

Is it running hot at speed ie 70 or just the same at slower speeds?


Looks like you checked some of the above.
Hope you find it before your hols

 

[dannyboy]

Sorry, dunno why photo didn't work. But suffice to say we are thermostat-less.

I think if the timing was out or the mixture was screwy I'd know about it from poor performance, don't you think?

I am suspecting something amiss in the cooling department...

Seems to be running hot at any speed

 

[dannyboy]

Yes, have vac advance. Will check that tomorrow as well. Sod it, looks like I'd better check the timing and mixture etc. as well. :roll:

 

[uber cool]

Have you checked that dip stick sender yet? Sounds a daft question but when you stick your head in the engine bay does it feel much hotter than before? An extra 30 deg c is quite a bit of heat. Is the bumper and valance hotter than before. I wouldn't dissmiss checking timing and fuel in the grounds it runs well. You can get better running on slightly wrong timing or weaker mixture.
It got to be fairly simple if ran ok before the engine was out

 

[dannyboy]

I think the bumper is hotter than before but can't swear.

Jobs first thing then:
- check the sender
- investigate whether any of the flap/linkage is there. I suspect not, being an ex-Aussie bus

Cheers

 

[dannyboy]

Sender working fine, indicating about 95 deg C in a boiling kettle.
No sign of any flaps or linkage.
Hmmm...

 

[71Westy]

Welcome to the running-hot-and-pulling-hair-out-trying-to-find-it club. Mine still runs 110-120 after removal, checking, and changing the oil cooler just in case. And it seems to run fine like that. Well it did until it seized solid on start-up - but that's got to be a different issue (just waiting for some time to pull the engine again). I run straight 30 oil - so don't think it could be that (been there!). The oil shouldn't break down until around 160 degrees I've been told, so I've given up and will just ignore the gauge (unless it zooms up).
Nick

 

[dannyboy]

Thanks Nick.
I'm beginning to think nothing may have changed since taking the engine out. It may just be hotter weather and me caning it a bit to make sure everything is "working".
I think I'll risk the 4 hour round trip I had scheduled for this afternoon and just make sure the temp doesn't climb up and up and up...
Dan

 

[dannyboy]

Well she coped admirably with the 250 mile round trip to pick up an ebay roofrack. Well worth the trip, it's looking even better on my bus than this pick of the seller's (sorry no pic of mine to hand).

On the M1 at 60mph on the GPS my bus is running at about 115 degrees. Push it up to 65mph and I get about 118 degrees indicated.

I've convinced myself that this is the same as before, now I think about it I don't think I'd done any extended "high speed" runs since I fitter the temperature gauge! Duh! A short burst and then back to less than 50mph and I'm not surprised I never saw over 95/100-ish. Paranoia induced by a) relatively new temp gauge to look at/worry about and b) knowing the family are relying on her for a 300 mile trip to Devon this weekend!

Thanks all.

Now, to sort what had better be the last problem before camping: blinking generator bearing has gone so gonna try and get the alternator conversion done tomorrow. Got the knackered generator out, broke the pulley pulling it off, think I've probably bent the axle as well so I'm guessing it's now a door stop

Wish me luck fellas - main thing I'm worried about is whether I've ordered every last little bit I need cos if it doesn't all turn up tomorrow we're going on hols in the Volvo.....

Cheers
Dan

 

[Merlydog]

Hi Dan, I have a temp gauge fitted. 1600 TP standard set up and mines always ran exactly the same temp as your describing. If I'm pootling the lanes it's about 80-90C, on a run at 60mph about 110C anything beyond 60mph and I'm in the 120C mark ish. If I drop the speed the temp drops too! Mines ran like that for 18months and been fine! Pressure sticks at around 1.5-2 bar on a long run.
I've got a France cycling trip coming up very shortly and I'm paranoid now lol :lol: :lol:

I did a little investigating and apparently the temp range of a vw air-cooled engine is 80-120C.. But I'm no expert and it was from a few different forums I read it! The actual temp vw intended them to run at, I have no idea.

All the best with the holiday matey and hope you get it sorted

Safe travels...

 

[dannyboy]

Cheers fella, reassuring.
Enjoy France.
Dan

 

[uber cool]

I think your right, nowt worse than watching the temp gauge rise!

On a 40mile run last weekend on the Motorway at about 65MPH mine was at about 220F which is approx 105C, but when it rose slightly higher to 225F i paniced and slowed down a little. Only fitted the gauge about 6 months ago, I might even disconnect as I wasnt bothered about oil temp before :lol: :lol:

 

[ibérico]

I think your right, nowt worse than watching the temp gauge rise!

On a 40mile run last weekend on the Motorway at about 65MPH mine was at about 220F which is approx 105C, but when it rose slightly higher to 225F i paniced and slowed down a little. Only fitted the gauge about 6 months ago, I might even disconnect as I wasnt bothered about oil temp before :lol: :lol:

I removed my gauge recently when I painted the dashboard... And I am back to relaxed driving!
I had about a year of stress looking at the temp gauge and I doubt I will reinstall it... Ignorance can be bliss!!

Good luck with the holidays!

 

[r73]

I think your right, nowt worse than watching the temp gauge rise!

On a 40mile run last weekend on the Motorway at about 65MPH mine was at about 220F which is approx 105C, but when it rose slightly higher to 225F i paniced and slowed down a little. Only fitted the gauge about 6 months ago, I might even disconnect as I wasnt bothered about oil temp before :lol: :lol:

Exactly the same here. Just done about 300 plus miles down to Cornwall and temp readings are 180-190F up to about 55 mph. 220F at around 60-65mph. And about 225-230F if I push the old girl past that.
I only really fit the gauges to check the engine out. Might remove them now tho cos you end up looking at them too much.

Don't worry bud - to quote 'creation blue' (just) on here 'get the first 10 miles out the way then sit back and enjoy the ride.'

Happy hols

 

[Trikky2]

I agree, gauges = paranoia :lol:

I never ran gauges until a few years ago when I fitted a "special" engine which I felt needed monitoring, both because of its capability and to protect the investment. Were I ever to revert to a stock engine I would not bother with gauges.

 

[ZedBed]

I'm a guage stripper too. My first bus had an oil pressure guage that gave me the willies. The engine ploughed on for years and was still going strong without the guage when I sold the bus. The oil light never came on. Good enough.

 

[71Westy]

OK, I've changed my mind.

I've had an old school VW repairer look at the remains of my engine, and what he found was interesting. The engine failed due to low oil feed to the main bearings (not bits in the engine as I thought). He thinks due to oil loss internally through other ill-fitting bearings (like the cam, which had been flapping about like mad). Plus using the original pump, which although not badly worn, wouldn't have been in its prime. Now the only symptom was hot running, likely as not due to the oil not being pumped round the system (and hence the oil cooler) properly.

So I'm sort of moving towards the "don't ignore the temperature" school of thought. I'm thinking that checking the oil pressure somehow would be worthwhile (it's been an expensive lesson for me).

Nick