rs2k
Chief Petty Officer
- Joined
- Aug 2, 2008
- Messages
- 486
I just picked up an early 80s Chrysler Challenger boat that had a fresh 30 over rebuild on the Chrysler 360 engine last year. The block was correctly winterized, but the previous owner neglected to fog or even cover the engine for the winter. When the previous owner went to go use it last week it was locked up. I bought it and decided to take it on as a project boat. I would appreciate any help or incite someone may have on this engine.
The block had clean and what looked like new motor oil in it. I pulled the plugs and worked the engine back and forth with a big wrench and a literal boat load of WD40, carb cleaner, and silicon spray penetrating fluid. After about an hour I got it to turn over with the starter just fine. After running a compression test on two cylinders (90 PSI and 60 PSI) I decided to pull the heads and have a look. It looks like the lack of compression came from the rusty valves. I could hear and see WD40 coming back out of the intake when doing the compression test like a valve was not seating. After pulling the heads I can see the valves are too pitted to get a good seal.
All the corrosion seems limited to the heads, carb, and intake manifold. The pistons looked brand new and the cylinder walls still had the honing marks. There was rusty WD40 around the sides of the pistons so I just kept spraying and wiping them with Carb cleaner until the cleaner came out clear.
The cylinder walls look to be in good shape except for some minor discoloration which cannot be felt with the fingernail and some minor corrosion where the rings were that can be felt my the fingernail. After really working one bit of corrosion with a load of paper towels and WD40 I was able to take it back down to the cylinder walls. I think taking a nice scotch pad to the walls will get them cleaned up again.
I'm a bit worried about the pistons rings. It took a lot of spraying to get the rust out of that location, but I'm hoping all the rust is from the heads and valves and not from the relatively clean cylinder walls and piston rings. After getting the heads fixed I plan on checking the compression again. If I don't get a good reading I'll probably pull the block and do a re-hone and re-ring job. I really don't think the block is bad enough to require re-machining at this point, but I don't know for sure.
The heads are another concern for me. There is no doubt that valves are toast, but is it possible I could just get by with just cleaning the heads of corrosion and replacing the valves? I having seen the valve seats yet, but everything else is in good shape.
I've always like the joke that a bad engine should be used as a boat anchor. The interesting thing is that this engine looks like it was used as a boat anchor. The rust was in large soft spots and looked like barnacles. It didn't look or feel like normal rust at all.
The block had clean and what looked like new motor oil in it. I pulled the plugs and worked the engine back and forth with a big wrench and a literal boat load of WD40, carb cleaner, and silicon spray penetrating fluid. After about an hour I got it to turn over with the starter just fine. After running a compression test on two cylinders (90 PSI and 60 PSI) I decided to pull the heads and have a look. It looks like the lack of compression came from the rusty valves. I could hear and see WD40 coming back out of the intake when doing the compression test like a valve was not seating. After pulling the heads I can see the valves are too pitted to get a good seal.
All the corrosion seems limited to the heads, carb, and intake manifold. The pistons looked brand new and the cylinder walls still had the honing marks. There was rusty WD40 around the sides of the pistons so I just kept spraying and wiping them with Carb cleaner until the cleaner came out clear.
The cylinder walls look to be in good shape except for some minor discoloration which cannot be felt with the fingernail and some minor corrosion where the rings were that can be felt my the fingernail. After really working one bit of corrosion with a load of paper towels and WD40 I was able to take it back down to the cylinder walls. I think taking a nice scotch pad to the walls will get them cleaned up again.
I'm a bit worried about the pistons rings. It took a lot of spraying to get the rust out of that location, but I'm hoping all the rust is from the heads and valves and not from the relatively clean cylinder walls and piston rings. After getting the heads fixed I plan on checking the compression again. If I don't get a good reading I'll probably pull the block and do a re-hone and re-ring job. I really don't think the block is bad enough to require re-machining at this point, but I don't know for sure.
The heads are another concern for me. There is no doubt that valves are toast, but is it possible I could just get by with just cleaning the heads of corrosion and replacing the valves? I having seen the valve seats yet, but everything else is in good shape.
I've always like the joke that a bad engine should be used as a boat anchor. The interesting thing is that this engine looks like it was used as a boat anchor. The rust was in large soft spots and looked like barnacles. It didn't look or feel like normal rust at all.
