Volkswagen Golf III - No compression @ cyl1 & 4 after wp/cambelt change

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Wed 21 Nov 2012 14:14
Volkswagen Golf III - No compression @ cyl1 & 4 after wp/cambelt change - McAge

Totally clueless after a waterpump and cambelt replacement, Mechanically done after all the possible rules and regulations.

The car is a Golf MK3 1.6 ABU engine (year:93)

What we have done:
Drove the (working and functiong) car into the garage and turned it of.
Aligned the markings on the camshaft and crankshaft.
Replaced the old waterpump and cambelt with the new parts. (the wp works as the tensioner on this model)
After putting everything back on the car starts with the gas pedal on 50-75%
Everything should work but it doesn´t
We have re-checked everything like 10-15 times and it should be working,
cam/crank at its markings makes the no 1 cylinder to be on the upper offset and the cam on offset för cyl 1.

It Sparks on all plugs, firing order on the distributor is 1-3-4-2 but still no compression on cyli: 1 & 4 (0 bar) and seems very high on cyl: 2 & 3 (about 13-14 bar)

Questions:
1. Is this a non-interference engine?
(If it is what can cause compression loss if not the valves can be crooked)

2. Any tips what i can do to solve this, i can't afford to turn it in to a shop just to eventually pay lots of money to know that the valves are damaged.

Wishing for a quick response =)

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Wed 21 Nov 2012 15:02
Volkswagen Golf III - No compression @ cyl1 & 4 after wp/cambelt change - Peter D

Did you turn it over by hand a revs before you tried to start it. Regards Peter

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Wed 21 Nov 2012 15:04
Volkswagen Golf III - No compression @ cyl1 & 4 after wp/cambelt change - Peter D

I do not understand this "cam/crank at its markings makes the no 1 cylinder to be on the upper offset and the cam on offset för cyl 1.

Regards Peter

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Wed 21 Nov 2012 15:15
Volkswagen Golf III - No compression @ cyl1 & 4 after wp/cambelt change - McAge

The markings (see picture at link)

art.rexbo.net/gates/jpg/200/5400.jpg

When these markings are aligned correctly the number 1 cyl shall be att upper offset ready to fire

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Wed 21 Nov 2012 15:07
Volkswagen Golf III - No compression @ cyl1 & 4 after wp/cambelt change - McAge

Yes we turned it over by hand before start and no suspicious sounds.

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Wed 21 Nov 2012 15:23
Volkswagen Golf III - No compression @ cyl1 & 4 after wp/cambelt change - Peter D

Set the markings up and check No1 is at TDC. Use a single strand of copper wire through the plug hole. Ideally you need to see the cam lobes to ensure No1 is on the compression stroke. Regars Peter

Edited by Peter D on 21/11/2012 at 15:27

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Wed 21 Nov 2012 15:40
Volkswagen Golf III - No compression @ cyl1 & 4 after wp/cambelt change - McAge

Set the markings up and check No1 is at TDC. Use a single strand of copper wire through the plug hole. Ideally you need to see the cam lobes to ensure No1 is on the compression stroke. Regars Peter

This have already been done several times, and with the valve cover off to see that it is correct. I have to excuse my poor technical english in this matter.


Do you know if this is a non-interference engine, wich means the valves can't get in contact with the piston if the timing is off?

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Wed 21 Nov 2012 15:43
Volkswagen Golf III - No compression @ cyl1 & 4 after wp/cambelt change - Peter D

And how the heck are you getting 13-14 bar. Amazing. Regards Peter

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Wed 21 Nov 2012 15:45
Volkswagen Golf III - No compression @ cyl1 & 4 after wp/cambelt change - Peter D

If the cover is off check the follower clearances as a bent valve would shoiw up with excessive clearance. Regards Peter

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Wed 21 Nov 2012 15:55
Volkswagen Golf III - No compression @ cyl1 & 4 after wp/cambelt change - McAge

I will check the clearence tomorrow and get back to you,

But i can't recall we missed that either.

Been checking things for 3 days now and the whole thing is a mystery

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Thu 22 Nov 2012 09:22
Volkswagen Golf III - No compression @ cyl1 & 4 after wp/cambelt change - thunam2

Reference more :
adf.ly/2038788/http://www.storingbooks.com

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Thu 22 Nov 2012 12:59
Volkswagen Golf III - No compression @ cyl1 & 4 after wp/cambelt change - 659FBE

I changed the cambelt on my son's 1.8 Passat of similar vintage without any problems. This engine may or may not be similar to yours.

One thing did stick in my mind though:

With Teutonic thoroughness, all shafts are marked. With Teutonic complete lack of imagination, the crank TDC mark is lost when you take the pulley off - so when you actually need it, it's not there. Genius.

It was a long time ago, but I remember realising this, and pulling the rubber plug out of the bellhousing to reveal the flywheel TDC marker "OT" and using this to set the crank. The camshaft has an obvious mark at the top and the jackshaft/distributor position can be set by using the scribed line on the distributor body which aligns with the rotor arm tip centre when cyl 1 is firing. Thanks, Bosch.

The engine fired up straight away and ran well until scrapped for other reasons. Beware the plastic tensioner wheel - rubbish. (Metal replacements are available).

This is an interference engine which, if mis-set will be bent.

659.

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Thu 22 Nov 2012 22:38
Volkswagen Golf III - No compression @ cyl1 & 4 after wp/cambelt change - Simon

The most obvious answer is that you have got the timing somewhat out?

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Sat 24 Nov 2012 14:15
Volkswagen Golf III - No compression @ cyl1 & 4 after wp/cambelt change - Peter D

I asume this engine has a woodruff key on the crank pulley. Have you checked the key is in place and intact. Regards Peter

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Sun 25 Nov 2012 11:34
Volkswagen Golf III - No compression @ cyl1 & 4 after wp/cambelt change - 659FBE

The cambelt wheel is keyed to the crank and is not removed to do this job. The aux drive pulley/TV damper assembly is bolted to the face of the camwheel with 4 x M6 setbolts. There is a locating peg to discourage mis-assembly.

659.

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Tue 27 Nov 2012 07:16
Volkswagen Golf III - No compression @ cyl1 & 4 after wp/cambelt change - Peter D

What is the status on this problem ??

Regards Peter

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Thu 31 Jan 2013 14:57
Volkswagen Golf III - No compression @ cyl1 & 4 after wp/cambelt change - sb10

This is an interference engine according to Autodata

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Sat 2 Feb 2013 21:24
Volkswagen Golf III - No compression @ cyl1 & 4 after wp/cambelt change - Crasher

VW list the compression pressures for an ABU engine to be as follows

Compression pressure:

New: 10...15 bar

Wear limit: 7 bar

Permissible difference between all cylinders: 3 bar

If the engine is timed corrcetly and you have no compression on a cylinder, the head will have to come off.

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