billthe3

Whats the best way to clean off all the carbon deposits and other crap on the cylinders while I have the head off the car?


While I'm putting these pics up, can any of you see anything noticable with the hg that would cause the bad compression on the #1 cylinder (the one on the right/front of the engine)?

Also, will this small scratch/mark in the number 2 cylinder wall affect anything? I can't feel it when I run my hand over it.

Pictures:
cylinder 1 (front of car)
cylinder 2
cylinder 3 (the stuff in the cylinder is just dirt that fell in after the head came off)
cylinder 4 (back of car)
all four cylinders (front = right)
scratch on cylinder 2

smac951

Lacquer thiner works pretty good.

Techno Duck

Seafoam works very well. Make sure you get all the crap out of the cylinders before you rotate the crank by hand.. use a shop vac to suck up all the carbon that comes off in chunks.

Kell

B-12 chemtool works very well, you can find it it most local autoparts stores.

KuHL 951

Bill,
How did the valves look on #1? Did you ever get that leakdown test done? Your compression was down (118 psi) but not like a totally failed HG. What does the flip side of the HG look like at #1? It could be you just have an under torqued head or a stretched headbolt or two. The overheating and bubbling in your cooling tract is usually a dead giveaway though. If you still have your head intact, turn it over, pour a little gas into the combustion chamber and see if it leaks past the valves through the ports.

hosrom_951

Great success with 3m scotch brite pads from the local supermarket, got the mating surface and pistons clean.

Does that score catch you're fingernail?

billthe3

Cool, thanks for the responses.

Hosrom - I'm pretty sure the mark in the cylinder wall does not catch my fingernail, but I'll check again tomorrow.

Steve - the headgasket doesn't look much different on the bottom side. I took these pictures probably two weeks ago and haven't really messed with the cylinder stuff since (been fighting with the exhaust/turbo), but I don't remember any noticable difference. As for the valves, I never did get around to doing a leakdown. I'll try the gas thing tomorrow and report back.

Here is the only pic I have of the head currently. I can't tell if its just the lighting/flash, but it looks like the intake valve on cylinder 1 (left side) may be sticking up some. I'll get some better pictures tomorrow.

If the valves are bad, I'm currently planning on getting a 5 angle valve job done as well as stiffer springs, so any issues will get fixed by those.

potent951turbo

Is there a safe way to get that ring of deposits off the top of the cylinder bores? I was just thinking about it the other day when someone asked about putting new rings in old bores and the majority said if everything looks okay just use new rings, but I would think you would need to clean off that ring of grime before removing the piston.

billthe3

I took a bunch of pictures yesterday of the bottom of the headgasket and the clyinder head, but my mom stole the camera so I can't get the pictures online till later tonight.

I did the fuel test and no visible amount of fuel leaked out through the valves, so I'm now really curious about why I was getting the bad compression. I'll take off the flywheel lock and turn the crank by hand to see if there is anything on the pinston wall that would indicate bad rings or something.

500

I had exactly that question when I was taking my engine apart. Normally one has to use a ridge reamer to remove that ridge of material otherwise the rings will snag it and possibly damage the lands on the way out. When I asked, everyone (including the Haynes manual FWIW) said that on these alusil bores, the wear is usually so minimal that it poses no problem. That was certainly the case with my 147k engine. The strip at the top was definitely colored differently, but it was almost undetectable by touch. My pistons came right out without the slightest resistance.

potent951turbo

Thanks for the info! I was thinking that also since I have seen people use the ridge reamers which cut a good bit a material away in the process of using one.

Perry 951

If you are to the point of having the pistons out (no other reason to touch the ridge) you should have the block on a stand and ready to send it out for a good clean up by the machine shop.

You need to be careful when cleaing internals. For the block, cover all the holes and the cylinders you are not working on at that time. This limits the possibility of getting junk in the oil pan, and then into your oil pump. You also need to protect the rings.

My tip:
1. With the piston all the way up in the stroke, fill the ring lands and the gap around the piston with Lucas Oil Stabilizer. This **** is so thick it will hold the junk in it when you bring the piston down.
2. Clean with a light abrasive and whatever solvent you choose.
3. Bring it down 1/4 stroke to clean ridge, reapply fresh goo, raise back up, and keep cleaning.
4. When done cleaning, rinse with Brake Cleen, wipe with liberal amounts of paper towels and make sure you get the top of the rings clean.
5. Add a little goo, roll down 1/2 stroke, clean, reapply goo, and move to the next one.
6. At final assembly, wipe the bores with a light coat of goo.