924Board.org

924ttrouble · Joined: 27 Feb 2003 Posts: 59 Location: Lacey, Washington

I can't seem to get the valve adjusted for the no.1 cylinder all other are fine. The intake valve is not adjusting it's either to loose or to tight. I know it says the the feeler gauge is 0.10mm or .004in I'm using the .004in gauge. I have no compresion on the no.1 cylinder. Help!!!

1982Porsche924 · Joined: 14 Nov 2002 Posts: 679 Location: Cupertino, CA

The actual valve adjusting bolt might have snapped. Also, have you checked with multiple feelers to see if it's adjusting at all?
_________________
1979 Porsche 924 "S"
Engine: Euro pistons, Light Flywheel, Weber TB, Bursch Header, Cam Wheel
Suspension: Front coil-overs, adj sways, Solid bush. Thicker tors. bars, 5-bolt, BBS rims
Body: Fiberglass widebody kit, 931 Nose

924ttrouble · Joined: 27 Feb 2003 Posts: 59 Location: Lacey, Washington

I don't think that the adjuster snap, I'll check it, is there a timing mark on the the crank pulley or is it some where else on the car? I don't or am not sure if I have the car set on TDC, I have no pressure on the no.1 cylinder to make sure I'm at the top of the compression stroke.

I think it's adjusting because it getting to tight or to lose. If it to tight, what will happen? If to loose what will Happen? will this cause no compression?

1982Porsche924 · Joined: 14 Nov 2002 Posts: 679 Location: Cupertino, CA

It shouldn't cause no compression, just valve noise. I would think slightly too loose would be ok (.120-.150mm). How did you check compression? Did you use a compression tester? What where the numbers?
_________________
1979 Porsche 924 "S"
Engine: Euro pistons, Light Flywheel, Weber TB, Bursch Header, Cam Wheel
Suspension: Front coil-overs, adj sways, Solid bush. Thicker tors. bars, 5-bolt, BBS rims
Body: Fiberglass widebody kit, 931 Nose

924ttrouble · Joined: 27 Feb 2003 Posts: 59 Location: Lacey, Washington

I have 95PSI on the other 3 cylinder and none on the no.1, I took the cam back off and check the tappetts and the all were set the same as far as I could tell. still no compression on the no.1 cylinder, beside that the car still won't start. Blown fuze in fuzebox No.8 fuze (replaced) I can't hear my fuel pump come on. This is getting fustrating and a little to comsuming for me.

I used the jumper I made for the fuel pump relay socket and still no fuel pump noise or not running. Now what is going on.

I had the car running before I pulled the head and change the two bad valves, now nothing. Can anyone help with this problem.

Does anyone know the post that showed the pitcures of the motor of 931 it's one of us and I throught I saved it but I didn't

CMXXXI · Joined: 05 Nov 2002 Posts: 1939 Location: Vicksburg, MS

I've never taken a compression reading on my car, but I believe others who have posted are in the 140-160 psi range. 95 sounds sorta low based on the other posts. It almost sounds like you've got a burned valve, thus no compression.

924ttrouble · Joined: 27 Feb 2003 Posts: 59 Location: Lacey, Washington

Thanks for the reply, but I still need answer to the other question. Yes 95 does sound a lot low I think it was about 125psi before I pulled the head off.

What am I doing wrong? I am a damn good mechanic, but this car is driving me crazy with all of it's funny quirks

Things just seem to keeping happen and I haven't even driving the car yet.

1982Porsche924 · Joined: 14 Nov 2002 Posts: 679 Location: Cupertino, CA

ummm, the car shouldn't be running with 95 psi.
_________________
1979 Porsche 924 "S"
Engine: Euro pistons, Light Flywheel, Weber TB, Bursch Header, Cam Wheel
Suspension: Front coil-overs, adj sways, Solid bush. Thicker tors. bars, 5-bolt, BBS rims
Body: Fiberglass widebody kit, 931 Nose

CMXXXI · Joined: 05 Nov 2002 Posts: 1939 Location: Vicksburg, MS

First things first. Get the crank and cam aligned at TDC, and the timing belt installed and tensioned correctly.

I'm confused with your posts...you say you "took the cam back off", and in another post you say "before I pulled the head off". If you pulled the head, then you are sure that a valve is not physically damaged, correct? Did you check for a crack or a hole in the piston? Even with bad rings, or a bad head gasket you should be getting some reading. But with low numbers on the other 3, I'm still thinking valve timing.
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'79 Eurospec 931

924ttrouble · Joined: 27 Feb 2003 Posts: 59 Location: Lacey, Washington

That's the point valve timing!! I don'tknow if it's correct I'm looking at the mark on the cam wheel and the postion of the rotor pointing at no.1 is this correct? No cracks or holes piston were fine head was fine changed two valves no.1 intake and the no.3 exhaust all other were fine. I could have had a weak battery when I was doing the compression test I was just checking for pressue on the cylinder. Why no pressure on the no.1 is beyond me. I pulled the head to change those two valves. I pulled the cam yesterday to check the tappetts on no.1 to make sure the adjustment screw wasn't broke.

Lizard · Posted: Mon Jun 30, 2003 5:24 am Post subject:

the only thing that I can think of that would cause zero compression is a bent valve, or the timing belt had been put on completely wrong but if you have a 931 that would mean bent valves
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3 928s,

78porsche924 · Posted: Mon Jun 30, 2003 10:29 am Post subject:

You said u pulled the head. I know this is kind of a stupid question, but u did use a new head gasket and aligned it right?
_________________
90 944 S2
78 924 NA <---now sold and killed by new owner
snailshell trans
Bae turbo kit
to check out my 944 S2 http://www.cardomain.com/member_pages/view_page.pl?page_id=388139

CMXXXI · Joined: 05 Nov 2002 Posts: 1939 Location: Vicksburg, MS

To properly align things for TDC (assuming that the camshaft sprocket and flywheel are correctly installed), slowly rotate the flywheel until the TDC mark aligns with the pointer when looking through the little window on the bell housing. I believe the mark is a "0" with a dash next to it, or a line under it. You can rotate the crank by attaching a 24mm socket to the main crank nut and slowly turing it while peeking inside the window at the same time. It's awkward, but can be done. You can use the notch cut into the crank pulley to get you close, but I don't think that using the crank pulley notch will be accurate enough to set the actual timing.

Once the flywheel is properly positioned, rotate the camshaft sprocket until the dot/notch on the backside of the sprocket lines up with the pointer on the housing. Then install & tension your timing belt and double check to make sure the marks are still aligned. Turn the crank two revolutions and verify that the marks still line back up after the two rotations.

Once these two are aligned, the distributor rotor should be pointing at position #1. You can also pull the #1 plug and shine a flashlight inside to see whether the piston is up top.

You say you replaced the intake valve on the #1 cyl... can you remove the adjusting screws completely and do a compression check? I've not done this, but wouldn't removing the screws completely prevent the valves from opening at all?

What I'm thinking is that maybe the valve you replaced has a stem that is too long, and is never closing.
_________________
'79 Eurospec 931

924ttrouble · Joined: 27 Feb 2003 Posts: 59 Location: Lacey, Washington

Yes I used a new head gasket and it aligned right and no the valve was not to long I matched it up with another valve from the head perfect match. When I do a leak down test on the no.1 cylinder I hear air coming out of the intake this I'm assuming is not right if both valves are suppose to closed, RIGHT!! Also the fuel pump was fried but I replaced it with one I found at my locale junk yard for $12.00 good deal.

78porsche924 · Posted: Tue Jul 01, 2003 10:54 am Post subject:

You might need new valve seats. The valve might be closing all the way but if it has nothing to seal onto...
_________________
90 944 S2
78 924 NA <---now sold and killed by new owner
snailshell trans
Bae turbo kit
to check out my 944 S2 http://www.cardomain.com/member_pages/view_page.pl?page_id=388139