hello all
my recently purchased vw buggy isn't firing in the #1 and 2 cylinders. upon inspection, the plugs are covered in oil.
is this a common occurance that has a easily diagnosed problem, or could it be a number of things.
the plan is to rebuild the engine over the winter months but i would like to ride a little now, before the cold.
seeing as i know nothing about vw engines, could someone offer some input for my problem, is it major, minor, should the engine be ran as little as possible?
i am slowly learning but at this point i have no clue.
thanks for any opinions/info and your time
oil fouled plugs
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guest from VA
my mistake, it is not the #1 and 2, its' the #3 and 4 cylinders.
the other plugs are firing and i determined this by removing the plug wire while the engine was running. #1 and 2 cylinders are firing and if you remove the plug wire(s) the engine slows down for each cylinder and dies if both are removed,
as for #3 and 4, the new plugs are gettin spark from the wires but the cylinders are not firing. no change in engine when plugs are removed.
the plugs come out oiled up, all black; the plugs aren't even hot.
#1 and 2 cylinder plugs are coffee brown and hot as hell so i know they are firing.
any suggestions?
thanks
the other plugs are firing and i determined this by removing the plug wire while the engine was running. #1 and 2 cylinders are firing and if you remove the plug wire(s) the engine slows down for each cylinder and dies if both are removed,
as for #3 and 4, the new plugs are gettin spark from the wires but the cylinders are not firing. no change in engine when plugs are removed.
the plugs come out oiled up, all black; the plugs aren't even hot.
#1 and 2 cylinder plugs are coffee brown and hot as hell so i know they are firing.
any suggestions?
thanks
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Guest
If you have a dual port engine, make sure the rubber boots on the manifold aren't leaking.
http://www.vw-resource.com/air_inleakage.html#test
http://www.vw-resource.com/air_inleakage.html#test
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wrench_monkey
- Posts: 119
- Joined: Sat May 29, 2004 9:18 pm
Since you've gone to the trouble to pull the plugs and clean or replace them and you know they are actually getting "juice" from the dizzy AND they are coming out "oily blackened" you probably have damaged valves, valve seats, valve guides or worn-out rings on the pistons.
You have mentioned you have a SP setup so you're running an earlier engine before the dog-house oil cooler was created. In these pre-doghouse oil cooler engines, the number 3 cylinder always ran hotter than the rest due to it getting the air AFTER the oil cooler had already been cooled. So it was normally the first cylinder to fail or loose compression etc.
It's odd to hear that BOTH #3 and #4 are doing this though....
That suggests something more common which would be a vacuum leak as suggested above by a failed intake gasket or in the case of a dual port also the rubber coupler before the end casting could be cracked etc.
The "oily blackened" description is the worst part since that means oil is literally getting into the combustion chamber somehow - piston rings keep the oil in the engine case and good valves, valve seats and guides keep the oil in the cylinder head. One of these two is not happening for some reason. With a loss of compression, the fuel will not be ignited and so you get the "feeling" of no ignition because basically you are not creating the pressure in the combustion chamber needed even though your spark plugs may be working properly... Hmmm? Did that make sense? No compression due to worn-out piston rings or a valve-related problem will stop the fuel from being combusted. This would fit your description of what's being experienced.
A compression test would help alot at this point to get a better understanding of what might be going on.
You probably shouldn't put any mileage on this engine if you hope to rebuild it until you discover why oil is getting into the combustion chamber just in case....
You have mentioned you have a SP setup so you're running an earlier engine before the dog-house oil cooler was created. In these pre-doghouse oil cooler engines, the number 3 cylinder always ran hotter than the rest due to it getting the air AFTER the oil cooler had already been cooled. So it was normally the first cylinder to fail or loose compression etc.
It's odd to hear that BOTH #3 and #4 are doing this though....
That suggests something more common which would be a vacuum leak as suggested above by a failed intake gasket or in the case of a dual port also the rubber coupler before the end casting could be cracked etc.
The "oily blackened" description is the worst part since that means oil is literally getting into the combustion chamber somehow - piston rings keep the oil in the engine case and good valves, valve seats and guides keep the oil in the cylinder head. One of these two is not happening for some reason. With a loss of compression, the fuel will not be ignited and so you get the "feeling" of no ignition because basically you are not creating the pressure in the combustion chamber needed even though your spark plugs may be working properly... Hmmm? Did that make sense? No compression due to worn-out piston rings or a valve-related problem will stop the fuel from being combusted. This would fit your description of what's being experienced.
A compression test would help alot at this point to get a better understanding of what might be going on.
You probably shouldn't put any mileage on this engine if you hope to rebuild it until you discover why oil is getting into the combustion chamber just in case....
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guest from VA
i dont' know a lot about the engines myself but i totally agree with you about it being the rings or valves.
i noticed that one of the tubes that go to the valves from the case( pardon my description of the part, i don't know what it is) on the #3 and 4 side is dented in a bit. i don't konw whats in those tubes but the dent seems like it would cause some trouble; and since that side is messed up, i would say that it has something to do with it.
the engine is on a used sandrail, so the damage to the engine in that particular area, on the underside, doesn't seem unreasonable to me.
thanks for everyone's help and advice.
i have contacted a fellow who will build me a new 1600 dp, turnkey for a super reasonable price. i think that is the way i will go on getting a running motor for the rail.
im new to these vw engines and i don't want my first one to be a bad experience for me.
i would rathert learn about the engine by doing regular maintenance and repairing what will gradually wear out as composed to learning about one by tearing down an old abused engine and rebuilding it as a first-timer and hoping that it will work the first time around,and it probably wouldn't without a lot of problems. plus i would probably end up sinkig more money into rebuilding the engine and getting it right that this new engine would cost.
one more question.
the engine will be a considerable distance away from me. not unreasonably a long way, but it would take up a day to get it; ~300 miles one way.
anyone familiar with the sw VA area and know of anyone that rebuilds engines, at a reasonable price?
thanks for all your time and info
i noticed that one of the tubes that go to the valves from the case( pardon my description of the part, i don't know what it is) on the #3 and 4 side is dented in a bit. i don't konw whats in those tubes but the dent seems like it would cause some trouble; and since that side is messed up, i would say that it has something to do with it.
the engine is on a used sandrail, so the damage to the engine in that particular area, on the underside, doesn't seem unreasonable to me.
thanks for everyone's help and advice.
i have contacted a fellow who will build me a new 1600 dp, turnkey for a super reasonable price. i think that is the way i will go on getting a running motor for the rail.
im new to these vw engines and i don't want my first one to be a bad experience for me.
i would rathert learn about the engine by doing regular maintenance and repairing what will gradually wear out as composed to learning about one by tearing down an old abused engine and rebuilding it as a first-timer and hoping that it will work the first time around,and it probably wouldn't without a lot of problems. plus i would probably end up sinkig more money into rebuilding the engine and getting it right that this new engine would cost.
one more question.
the engine will be a considerable distance away from me. not unreasonably a long way, but it would take up a day to get it; ~300 miles one way.
anyone familiar with the sw VA area and know of anyone that rebuilds engines, at a reasonable price?
thanks for all your time and info