QuestionQUESTION: Hello Howard,
I have a bit of a story to tell you, and would like your advice. In the course of having my 1980 MGB engine rebuilt, while the transmission was detached, I had a local reputable transmission shop inspect the transmission, replace seals, etc., because I wanted to try to ensure there would be no problems with it after reassembly. They told me they found no problems - cost me around $700. The shop's stipulation was that it had to be removed from the car and delivered to them for them to look at it, which was fine since it already was. This was last year about this time.
Since then, after getting everything back together, I have had many problems with other things on the car - many you have helped me with. But I still have an oil leak, and after cleaning and driving and inspecting have found oil leaking from somewhere in the transmission/overdrive area. I thought is was the overdrive since there was a thick film of oil hanging to the bottom plate of the overdrive - the plate with the model and serial #s on it. There was oil all around that area under the overdrive. There were also a few drops of oil hanging to the bottom of the weep hole at the front of the transmission.
I took the car to the transmission shop today. They looked at it and agreed there is oil leaking - not sure from where. They thought it may be from the top near where the gear shift lever is attached, since they showed me where oil was down the side of the transmission below the gear shift lever. They could not see above - even using a mirror.
Bottom line - they will fix it if I take the transmission out and deliver to them. I don't really want to go through all of that again if I don't have to.
Questions:
1. Is there something that can be checked for the leakage I have tried to describe above - and repaired without removing the transmission?
2. Can the transmission be removed without removing the engine?
3. Any other advice?
What would you do?
ANSWER: Hi Wayne,
The only way you can look for oil leaks is to wash the transmission first and put it up on a lift and have someone run the car in high gear in overdrive while you watch closely with a strong light under the car. I assume you have not over filled the transmission with oil right? The overdrive unit is a two speed automatic transmission on the rear of a straight stick 4 speed gearbox. So when the OD is working there is oil pressure and thus possible leaks. Unless you find some loose bolts that you can reach from under the car it will need to be removed by removing the engine.
By first washing the trans, and running it on a lift, you should be able to isolate the area that is leaking. Driving the car is not useful because air moving under the car will spread the leaking oil to a different area than where it is coming from.
Howard
---------- FOLLOW-UP ----------
QUESTION: How could I have overfilled the transmission with oil? And how can I check that. I thought that it was to be filled until it was to the bottom of the plug - and any excess would run out?
ANSWER: Ok, never mind the over fill as a problem (the older MGBs had the filler plug on the top) As long as you know it was filled while in the car.
---------- FOLLOW-UP ----------
QUESTION: I filled the trans after I bolted it to the engine but before I put it in the car. That presented a bit of a problem as oil ran out of the speedo connection hole as the whole thing was tilted to install. I plugged that up until I got it in place. I then removed the fill plug on the trans to let any excess drain, because I did noy know if I had it at the right angle while filling. I don't remember how much,if any, excess drained out but it was very little. Since then the car has been driven over 800 miles. Do you think it possible there is too much oil in the trans or overdrive? I guess I am hoping you will answer yes (although I don't think you will), as this would be the easy solution.
AnswerIf you opened the fill plug after you had the engine installed and let any excess drain, you are ok on the "possible overfill". Proceed with washing the trans down with any detergent or a spray can of "Gunk" works well. Then hose it down with water and let dry. Put the car on a lift or if you don't have access to a lift put it up un jack stands. (NEVER get under a car on a jack) Then run the car in high gear in overdrive for several minutes and then get under the car and inspect it with a strong light. If you still can't tell where it is coming from, try some auto parts stores for a dye that is put into oil to locate minor leaks. This was the procedure we had to use in the dealership.
Driving the car to check for oil leaks on a trans is not a good idea because the strong air currents will spread the oil out and force it to a different location.
Howard
