tb

Hi there, I was hoping someone on here might be able to help me out. I just did the head gasket in my 22re. I did the head gasket only and not the timing chain, because it had just been done.

It had a really tough time starting (required carb cleaner). Once it starts it runs perfect with the exception of a very loud knock that wasn't there before. It almost sounds like a compressor. It also starts right up if its warm.

Everything was torqued to factory spec. I had the head checked and re-surfaced at the machine shop. Timing is correct. I adjusted the valves to factory spec. I'm going to re check them once the engine cools off but this knock seems to be louder than just valves.

If anyone has any ideas they would be much appreciated. Thanks.

putneysmachine

While the truck is running, pull off one plug wire at a time (pulling the wires off at the distibutor cap is easiest) see if the knock goes away, if so, you probably have a bad bearing on that cylinders connecting rod. If the knock is still there, you might have something in one of the cylinders (nut, washer, old gasket debris).

I've found copper washers, steel washers, old compressed headgasket material...etc embedded into the piston / head after people have replaced headgaskets. It will cause a knock that sounds similar to a bad bearing. It's easy to forget to check every port on the head and port on the intake manifold before re-assembly.

You can pull out one spark plug at a time and look into the cylinder bores to see if there are any "fresh" hammer marks on the tops of the pistons.

Did you check the condition of the timing chain guide rail? If it is broken, the chain will slap around a bit (onto the inside of the timing cover). It is a higher pitched sound, less of a knock noise.

tb

Thanks for the reply. I ended up adjusting the valves and drove it around for a bit and it runs like new. I'm still having trouble with cold startup though. I checked the cold start injector and injector timer and both are showing the correct resistance. I suppose I'll trace them back to the ignition switch and make sure everything is correct.

Does anyone have any other ideas on what it may be?