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Author Topic: Slight overheating - pump timing?  (Read 5154 times)

Reply #15February 06, 2012, 05:55:19 pm

regcheeseman

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Re: Slight overheating - pump timing?
« Reply #15 on: February 06, 2012, 05:55:19 pm »
I'm running 155bar injectors instead of the 135s the pump had originally.

Internally the pump is spot on, the engine has just been rebuilt and the cam timing is bang on.

I was turning the motor on the cam pulley so that would equate to a small difference.

It is definitely running hot though - the previous 1.6 engine pegged the gauge at a fraction under the halfway mark. The 1.9 is fine until you start to push it. I've bought a performance rad and new low temp fan switch - hopefully that will keep it in check.

Reply #16February 06, 2012, 09:41:35 pm

Mark(The Miser)UK

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Re: Slight overheating - pump timing?
« Reply #16 on: February 06, 2012, 09:41:35 pm »
Getting a rad for the car with a/c should give you the extra cooling.

For an injector to require your pump to be advanced to 1.2 ish, would require the injector to be opening with a way higher bar, say 200 ??? So I think not.

I suspect that he dynamic advance is lagging where it should be. Have you checked internal pressure v rpm, or even got figures for dynamic advance?

Have you or anyone come across a GTD operator's handbook?
« Last Edit: February 07, 2012, 05:49:23 am by Mark(The Miser)UK »
Mark-The-Miser-UK

"There's nothing like driving past a bonfire and then realising; its my car on fire!"

I'm not here to help... I'm here to Pro-Volke"

Be like meeee: drive a Quantum TD
 ...The best work-horse after the cart...

Reply #17February 07, 2012, 12:24:25 am

Baron VonZeppelin

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Re: Slight overheating - pump timing?
« Reply #17 on: February 07, 2012, 12:24:25 am »
In the past i've read about how over advanced timing raises cylinder pressure (and heat). Can't remember the numbers / percentages.
But they go up fast. Its not a good environment.

There's most (if not all) of the heating symptom you have.

Is this the 1.6 block / 1.9 head engine you mentioned in another thread ?

Where it stands, i'd put the 135 bar Injectors in and have another go with it. I understand the advantage of a better/bigger radiator - but i think you need to get the cylinder pressure back down to deal with the heat at the source. Before other issues arise.

Between the internal pressure and the 135 bar Inj's something should reel it back in.

Reply #18February 07, 2012, 08:08:03 am

theman53

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Re: Slight overheating - pump timing?
« Reply #18 on: February 07, 2012, 08:08:03 am »
pegged the gauge? so it was running 284F?
I really think the gauges in these cars create worry. If you don't have some type of gauge to be able to measure the actual number you maybe chasing your tail. I had a flat red bunny that would run 2 lines down from the red line on the gauge, but you could take and put your finger in the expansion tank. You couldn't hold it there, but it wasn't bubbling over or too hot. A number of how hot it is could give us a base to start with.

Reply #19February 07, 2012, 09:47:53 am

regcheeseman

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Re: Slight overheating - pump timing?
« Reply #19 on: February 07, 2012, 09:47:53 am »
no, not pegged the gauge as in maxxed out.

As in the needle sat at halfway and didn't budge, maybe creep up 1mm on a long hard climb

As soon as the 1.9 went in the guage would stay in exactly the same place until the motor was pushed hard when it would climb rapidly and seemingly burp a bit of coolant out of the rad (no header)
After a few times doing this the coolant would be getting low and the overheating would get progressively worse, I never let it get into the red.

Quote
Is this the 1.6 block / 1.9 head engine you mentioned in another thread ?

Same head but with a 1.9 block and the 1.9 injectors

I'll set the timing back down to 1.00 and see how it goes....

Reply #20February 07, 2012, 04:34:40 pm

Mark(The Miser)UK

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Re: Slight overheating - pump timing?
« Reply #20 on: February 07, 2012, 04:34:40 pm »
no, not pegged the gauge as in maxxed out.

As in the needle sat at halfway and didn't budge, maybe creep up 1mm on a long hard climb

As soon as the 1.9 went in the guage would stay in exactly the same place until the motor was pushed hard when it would climb rapidly and seemingly burp a bit of coolant out of the rad (no header)
After a few times doing this the coolant would be getting low and the overheating would get progressively worse, I never let it get into the red.
Is this the 1.6 block / 1.9 head engine you mentioned in another thread ?

 Same head but with a 1.9 block and the 1.9 injectors

I'll set the timing back down to 1.00 and see how it goes....

Quote
Reg
If you're set to 1.2 with 155's then going to 135's could EDIT effectively put you up to the equivalent of 1.3 to 1.4 if you were staying with the 155's:o
Run the engine and with the pump bolts loose swing pump to get the 'tuned position. Repeat at fast idle incase there is some difference, which there may be if your pump is not advancing correctly.

Back to your burping problem:
Can you be sure that you don't have a slight head gasket leak, that only shows up under reasonable loading?
« Last Edit: February 10, 2012, 06:51:57 am by Mark(The Miser)UK »
Mark-The-Miser-UK

"There's nothing like driving past a bonfire and then realising; its my car on fire!"

I'm not here to help... I'm here to Pro-Volke"

Be like meeee: drive a Quantum TD
 ...The best work-horse after the cart...

Reply #21February 09, 2012, 11:31:20 pm

Baron VonZeppelin

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Re: Slight overheating - pump timing?
« Reply #21 on: February 09, 2012, 11:31:20 pm »
135's run a lower timing spec than 155's.
Seems he could run lower timing with 135bar, not higher ?

But its no big deal - unless he needs to go that route.

Reply #22February 10, 2012, 06:42:13 am

Mark(The Miser)UK

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Re: Slight overheating - pump timing?
« Reply #22 on: February 10, 2012, 06:42:13 am »
135's run a lower timing spec than 155's.
Seems he could run lower timing with 135bar, not higher ?

But its no big deal - unless he needs to go that route.

I totally agree Mr Baron...
My point was intended to say that with the already high setting for 155's, it would effectively be like running with further advancement, like 1.3 to 1.4 [for the 155's], if 135's swapped in.

I will edit my previous post so that it reads correctly ;D
« Last Edit: February 10, 2012, 06:54:27 am by Mark(The Miser)UK »
Mark-The-Miser-UK

"There's nothing like driving past a bonfire and then realising; its my car on fire!"

I'm not here to help... I'm here to Pro-Volke"

Be like meeee: drive a Quantum TD
 ...The best work-horse after the cart...