Need help getting 944 na to run correctly

jkrustchinsky · 08-27-2008, 12:21 AM

Heres the whole story, me and a friend tackled the timing belt, whilst pulling the belt off we accidently took the car out of time. So we spun the crank manually without a belt and hit TDC. we then spun the cam manually and aligned the tdc marks.

we assembled everything and tensioned the belts and started her up, it made a pinging noise so i shut it down immediatly. It was at that moment when we knew the timing was off so we dissasembled everything again.

I found that it was about 5 teeth advanced at the cam with the crank at TDC. I then slipped the belt off the cam and aligned up the tick marks. I reassembled everything and started her up,

The car runs smooth, idles, but makes a odd tick sound, can hear it with the hood closed but barely when inside of the car with the windows down. I believe i am about 1 tooth off on the timing still,

Heres the thing, do you guys think i did any damage, it runs good, and drives good, oil pressure is good. Just makes the noise. I know it was stupid but i didnt figure out until afterwards that you cant spin the crank with no belt on.

is it correct to adjust the cam timing but manually turning the crank with the belt on to TDC, and then slipping the belt off of the cam sprocket to manually turn it to align the tick marks? Please help, car is my daily driver, and i feel like a retard. I know its an interface engine but my stupidity kicked in hard last night. Thanks, Josh

Jeff Laurence · 08-27-2008, 05:13 AM

If it idles and runs correctly, you MAY have dodged the bullet. I don't think it would idle with a bent valve.As a check you could do a compression or leak-down test. Could the ticking sound be a lifter or an injector?
Good luck,
Jeff

jkrustchinsky · 08-27-2008, 05:18 AM

i was thinking it was loud injectors too, im gonna retime it anyway. all i need to hear from you guys is i dodged a big ass brown bullet with leather interior, thanks, Josh

John_AZ · 08-27-2008, 06:04 AM

Josh,

You need to do a compression test.

Reset the belt, crank at TDC and cam marks set, with the plugs out and turn the crank slowly to see if you can "feel" any interference or binding due to a bent valve. You have run the engine and that is a good sign. Since you immediately turned off the engine----at idle--when you heard the first sign of trouble, you may have a 30-70 chance of no bent valves (optimistic). Typically one intake & exhaust goes. With the cam housing installed on the block, there are always valves open.

The crank and cam can be turned separately to align the timing marks. Carefully.

Good Luck.

John_AZ

Rasta Monsta · Rasta Monsta's Garage

+1 on the comp test, unlikely you avoided damage. Good news is people are giving away 2.5 heads these days.

many944s · 08-27-2008, 06:56 AM

+2 on the leak-down!
It sounds like you *may* have dodged the bullet. About %80 percent of the heads I rebuild have at least 4 valves bent... usually the exhaust valves. Not to bring you down, but I have even found "slightly" bent valves that actually pull down against the valve seat because there is enough force from the valve spring to bow the stem enough to allow the valve to seat! In this case however, there is noticeable leakage that would be detected by a leak-down test, as the valve doesn't seat completely, but it is DARN close!!

Good luck, and let us know how your leak-down goes!

-Nick

jkrustchinsky · 08-27-2008, 09:13 PM

thanks for the help guys, we dodged a bullet here, shes timed PERFECTLY, and she runs great, no noises. thanks, Josh

John_AZ · 08-28-2008, 04:45 AM

Quote:

Originally Posted by jkrustchinsky

thanks for the help guys, we dodged a bullet here, shes timed PERFECTLY, and she runs great, no noises. thanks, Josh

Josh,

Quick! Go to a casino! Buy a lottery ticket! Ask for a raise! You only have a short time before this magic passes!

Great.
John_AZ