- This topic has 10 replies, 4 voices, and was last updated 9 years, 9 months ago by
.
-
Topic
-
Vehicle 1992 Dodge Grand Caravan. 3.3L 420,000 miles 🙂
In a previous thread where I discovered a Rocker arm had a hole worn through it. I replaced all 12 on 1 side. However, It also appeared that oil was not flowing very well. Now, 2.5 months later I have been hearing squeaking and ticking. After pulling the oil cap off, I saw the rocker arms and shaft completely dry! Oil pressure is OK. Is this most likely a blockage? Is there much hope of fixing this issue without pulling out the engine?
Front/dry rockers:
Front shaft wear:
rear rockers:
-
Replies
-
In your engine, rockers are oiled through the shaft. It is possible that a blockage or RTV booger could be blocking the oil from reaching the rockers. If you remove the shaft assembly, you will see an oil hole from the head to the shaft. I’d start looking for a problem in that area. This passage from the head, or the shaft itself, could be plugged up.
I pulled the shaft off and see where the oil should be coming up through one of the bolt holes. The holes are over sized enough that it appears the oil is intended to flow around the sides of the bolt. I blew some compressed air down the hole and it definitely flows through the hole. I also ran a wire as much as I could in hopes it would find any clog and help clear it. However, after putting a new rocker arm shaft in place I ran the engine with the valve cover off, and could see NO oil flowing. I took the bolt off to look down the hole and again NO oil.
I guess this is a very bad sign?
If there was a blockage I would think the oil pressure would be abnormally high.
You could try some trans fluid in your oil. Let it run for a bit. This should probably be a last resort though.ATF might work, although I would be tempted to use a stronger solvent such as Berryman B-12 or a quart of motor flush. Oil starvation is a big problem. If it can’t be cleared using solvent and oil changes, a rebuild may be the only way to fix it. You may want to pull the valve cover on the other bank to see if they are dry too.
I wonder if you could pull the oil pan and pump and spray some acetone or something down the oil passage way then let it sit over night.
UPDATE: (See first post for pictures) I pulled off the rear cover and it appears it also has issues. Massive amounts of sludge. It appears wet with oil, but also lots of rust, so I suspect it is also not getting the proper amount of oil. I’m curious if the path for the oil for the 2 sides meet up and is shared at some point. I would suspect this is the path that is blocked. Is it possible some component wear would cause the the path to be blocked by some other engine component?
The oil to the rocker arm shafts is provided by pressure created by the camshaft bearings. The camshaft bearings have holes in them that allows the oil to move to the rockers. If the cam bearings have spun a little, the holes could be blocked. Or, the cam bearings are so worn that they are incapable of moving oil to the rockers due to the clearances being too wide.
[quote=”cap269″ post=130999]The oil to the rocker arm shafts is provided by pressure created by the camshaft bearings. The camshaft bearings have holes in them that allows the oil to move to the rockers. If the cam bearings have spun a little, the holes could be blocked. Or, the cam bearings are so worn that they are incapable of moving oil to the rockers due to the clearances being too wide.[/quote]
I suspect this is what happened. I made some fairly extreme attempts (short of taking more than the valve covers off) to flush the oil passages in case it was just some gunk causing a blockage with no success.
I have now moved on to my 1997 Caravan I had sitting, waiting for my 1992 to finally die. At only 118,000 miles, it feels like a brand new vehicle to me 🙂
From your description it appears the engine has become so sludged up multiple oil passageways are plugged. The only solution is for the engine to be cleaned and that requires disassemble]y and rebuilding. I have done this courtesy of a certain oil company which put out bad product and it is no fun. I’d suggest an engine swap if you want the vehicle to run again.
- You must be logged in to reply to this topic.