BAD metallic click in 1994 SC2

tallguy67 · 05-16-2004, 09:08 PM

I started a discussion last week about head-gaskets and valve replacement because I have a HUGE metallic click in the top end of the engine and I thought I had broken a valve due to a cylinder full of coolant due to a bad head gasket. I pulled the cam (valve) cover off this morning and there is no way that is the problem. Here is what I found.

The metallic click seems to come from directly over the cylinder (we'll call it #2 since it is the second one in on the passenger side of the car). The click occurs exactly 4 times for every time the cam-shaft turns over. Since the cams turn over at half the speed of the crank, that means whatever is wrong is happening twice per revolution. Also, every time it happens the timing chain gets a little slack in it, almost like whatever is causing it is hesitating in the front half of the chain.

If anyone has any suggestions about diagnosis, then I would be very appreciative. I am afraid that a mechanic is going to want to tear the head off the engine to diagnose this and around here that costs about $1000. The car has about 150,000km on it and is starting to show signs of a bad CV joint, muffler pretty much rusted out and a slight leak in the tranny so I would like to know what I am in for before I start sinking $$ into it. I hate throwing good $ after bad so if the engine is in real trouble I will cut my losses and start looking for something else.

I really would rather not do that though, so if anyone with experience with the DOHC eninge in the SC2 has any suggestions I would love to hear them.

Thanks,
Sean in Calgary.

RiceRocket · 05-16-2004, 09:12 PM

I'm thinking a timing chain guide....

Joeybagodonuts · 05-17-2004, 01:36 PM

before you spend a thousand or more tearing into a old motor, you can get a complete 94 series for about 500.00 with us, or most people nowadays are opting to use the later model engines.
if its JUST a timing chain and can be repaired you have to weight your options, if doing it yourself you can be done for about 200.00, if paying someone its going to be anywhere from a low of 500-900.00 depending on the shop/dealer
let us know what you find, for 700.00 you can have one of our low mileage later model engines and not have to worry about it.

tallguy67 · 05-20-2004, 03:35 PM

Well, I got this problem diagnosed and fixed. I owe a couple of people (on this board and off) mental apologies. All were pointing me in the direction of timing chain guides and tensioner. I was being stubborn, darn it, the sound was coming from somewhere in the valve train. I finally gave up and took it to my neighbourhood garage. The owner and his lads all seem to do good work and never try to have one over on you. After about an hour of diagnosis, turned out to be broken timing chain tensioner and destroyed guides. He snagged the whole replacement kit from Saturn (amazingly their price was better than aftermarket folks - NAPA etc).

WOW, what a difference. For about the last 6 months I have had a rattling sound (again sounded like valves) when I first started the car. After 2 or 3 mintues it would go away. That light rattling as well as last week's rather catastrophic sounds are all gone. The car sounds like it has a brand new engine under the hood.

I guess a sort of old dog, learned a new trick this week.

Now, if only these cars were as easy to work on as my 1957 IH Tractor. Those things were built to last. Although I guess a top end of 1900 rpm will tend to stretch out the lifespan of a power plant.....

Thanks for everyone's help in this and the other thread I had going on a related problem.

RiceRocket · 05-20-2004, 10:34 PM

Quote:

Originally Posted by tallguy67

Although I guess a top end of 1900 rpm

That isn't that much lower than the SOHCs....

jeep45238 · 05-21-2004, 01:54 AM

1900 RPM vs 5600 (can't remember?) RPM.....BIG difference.