I recently purchased a 98 SL1 with 105K on the clock for my daughter. I gave it a good degreasing, put it on the lift and did a visual inspection including a compression test, brakes, coolant, suspension etc. etc. all looked pretty good. A couple of weeks ago it started using a little coolant and then more until the water pump was leaking out the weep hole pretty good so I bought a new pump and when I removed the old one it had oil mixed with coolant in the cavity also some water has made its way into the oil
(not milky in the sump but pretty good condensate build up in the valve cover). To make a long story shorter, today I did another compression test (195-200 on all cylinders) and then removed the head, the head is straight and had good sealing around the cylinders but it looks like previous owner put stop leak in the coolant. I have read that these engines have head cracking issues. So my question is does the block also have cracking issues. I have seen Clearwater cylinder head in Florida has new complete heads for $335 + 25 shipping but I don’t want to throw good money away if the blocks are also prone to cracking.
Thank you,
Alan

 

The SOHC heads are most definitely prone to cracks. Don't see too many posts where cracked blocks have truly been attributed as the cause of death.

The SOHC head cracks can start out as very fine and difficult to see.

You did not indicate that the car has overheated. How did the head gasket look when you pulled the head?

Stop leak is not a good sign -- but it may have been added to address what became your water pump issue....

 

Yes I believe it was low on coolant and overheated. After talking with her last night she said she got a temperature light but the gauge was fine so she kept going. I explained if she was low on coolant and the sensor is in air it’s possible for the gauge to not read correctly and you should stop.

As for the head gasket all the sealing areas looked good but it had particle buildup at the coolant ports mixed with oil that looked like crack sealant. On the cylinder head there was some buildup outside the combustion sealing ring of the gasket that looks like corrosion, it has a greenish tint. Cylinders barely look worn at all and still have cross hone marks in them. I took pictures but they are at my shop. I checked the head with a Starrett precision flat bar and could not see any light. My first thought was warped head /bad head gasket but now what I am wondering is where the head cracks are and would they allow oil from a pressure port into the coolant.

(Previous owner had a receipt for a water pump and a belt 1 ½ years ago.)

 

OK, so after talking to a couple of cylinder head guys the SOHC head apparently has porosity and cracking issues. I am told that most often is by the #2 cam tower and can lead to oil in the water. Clearwater cylinder heads offer a sand cast after market complete head with a 5 year warranty for $335 and my wholesale price from Saturn is $480 so I guess I'm going with the sand cast head.

 

please let us know how it works out -- it'd be great to have another confirmed reliable source for these heads....

 

Cylinder head looks great. Only things it doesn’t come with are the int./exh. studs and coolant sensor. Car is back together and runs well.

 

Hurrah!! Glad you are back on the street. It looks like we may have a brand new source for cylinder heads ......

 

sweet -- I have a spare block I want to build up outside the car but I don't have a head for it...I was hoping we'd find a source for NEW heads (as opposed to the reman ones from Saturn)

Glad to hear you are running again....