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MG TD TF 1500 - Oil pressure (yea another question)
|Have read all the archives for issues relating to new engine start up. Have tried all the advise with the exception of the ones relating to pressurizing the oil Gallery, still can't get pump to prime. Cannot get any oil to come out the pump to filter tube (early TD) at all.|
I am going to try again tomorrow, but if I don't get oil pressure, what other issues do I need to start checking?
BTW. Engine was rebuilt by the PO. Never run. I took off the pan and checked out as much as I could and did not see any issues with the rebuild.
|Try the turkey baster in the upper banjo bolt... it worked for me.... couldn't get prime bolt off pump.|
After pumping a bit...back off the oil filter cover and listen for a little bit of air escaping... (did you soak the oil filter before assembling?
Anyway...worked for me.
|The turkey baster is a good idea but I leave them to turkeys, master cylinders and Chrysler power steering pumps. A cheap quick and clean way to prime the system (or at least it worked for me) is to use a marine lower unit grease pump. They can be bought at any marine store or dept. store during boating season for under $5. Remove the brass plug beside the oil canister, and put the plastic hose in. The other end screws into a quart oil bottle, then simply pump up the system. |
In Gordon's case, you could take off the bajo bolts and prime both top and bottom by inserting the tube in one hole, then the other.
Bruce, did you replace the gaskets after the pan was off? If the gasket doesn't have a good seal at the pick up hole or the gasket are reversed (pick up hole is covered) you won't get any suction.
|Some years ago, a client of mine asked me to investigate why he had no oil pressure on the engine in a TD he had just bought on a whim. The people from whom he had bought it, told him they had rebuilt the engine but were having trouble in getting oil pressure. Despite this, he bought the car and tried himself, unsuccessfully, to get oil pressure.|
After I had tried all the "usual" methods and still failed, I removed the engine and discovered that the previous owners had replaced the sump with "home made" gaskets. The hole, which allowed the oil to flow from the sump pick up into the pump's body had not been cut so, of course, there was no way in which any oil could have been passed around the engine!
During their attempts to get oil pressure, by running the engine, most bearings had been destroyed and damage had occured to the rockers and shaft bearings.
Because of the crude manner in which the gaskets had been fabricated, there was also a substantial risk of a large oil leak at the rear end because the small "ears" which engage with the rear main bearing cap were non-existant.
Moral? Check everything any DPO does.
|Welll, frustration has taken over. Tried everything and still no oil pressure. So looks like I will have to start by pulling off the oil pan. I installed the oil pan gasket when I looked at the PO's rebuild work. I paid special attention to getting the gasket correctly aligned over the oil hole so am pretty sure that is not it. As this is the earlier oil pickup, I wonder if it may be hitting the bottom of the pan and not allowing any oil to be picked up?|
Also have to consider that the oil pump is not working. Wonder if the PO forgot the drive key on the oil pump shaft? Is there a way to check if the gears are turning? Also, can you pull the oil pump without fully taking out the engine?
|Try this before pulling the pan- remove top pump banjo bolt and using pump oil can or whatever, keep it full and turn the engine backwards slowly, while adding oil to overflowing (put in 4th gear and roll car backwards). Do this several times. This should pump oil backwards down the pickup tube and fill the pump/gears. This works on my car. If the oil isn't sucked down, something is wrong. A car in town here many years ago had the oil passage through the pan blocked by too much silicone sealer.|
|One thing that you might check is that the relief ball bearing and spring in the pump are seating properly.|
After a re-build some years ago, [and after driving the car for about 15,000 miles], I had a fast loss of oil pressure and then no OP at all.
When I checked the pump there was a small piece of what looked like spilt-pin, in the relief valve.
How it got there I will never know it must have been in tucked behind the spring and eventually found its way out.
Also I don't know how long you're turning over the engine? On an oil and filter change I guess it takes me about 30 seconds to show pressure in the gauge. After an engine rebuild, much longer.
Also, providing that the plugs are removed and the engine has not been standing for a long time and is still lubricated, little damage will be caused by turning it over on the starter for quite some time. After all oil pressure is only required to overcome centrifugal force.
The gears can be checked by loosening the faceplate and turning the engine by the staring handle. But for them not to be working then somehow the drive shaft would not be engaging with the gear on the cam shaft and thatís unlikely.
I guee you've chaked that the oil pick-up pipes in the sump are clear?
It is possible to remove the pump without removing the engine, but itís difficult despite what the manual says. On LHD cars you have to remove the steering column.
Best of luck.
I rigged a way of pressurizing the oil gallery by fitting a tube to the brass pulg hole above the pump. By using a oil jug fitted pump, I was able to push oil from the plug up through the lifters. I would assume this would also get oil to the cam, so not too worried about wear. Also filled the pump from the lower oil pipe, put the car up on jacks and in first gear turned the engine backwards.
Rechecked the lower pump fitting and it was still full. Tried the starter a number of times and still no pressure.
Will pull the check valve and the pan this weekend. If I find all ok there, will have to look at pulling the pump. Just got to believe either the cam ingagement gear is turning on the shaft or the PO did not install the key on the oil pump gear.
BTW. Alos disconnected the oil guage hose just to assure it was not the guage.
|Definitely look at the relief valve and make sure the ball/spring/guide are there and in place. If it is there, then off with the pan, etc. Did you happen to see the show with the Boyd Coddington hot rod that had the same problem? If he can have it happen that should make you feel better!!|
|I did see that. My old engine actually had the later model oil pickup with the horn on the bottom (even though it is actuall older than current engine). This unit, with the open round pickup, could be against the bottom. My old oil pickup was destroyed when the rod let go. Have to see if I can figure out how to put the horn on the current pickup. |
Lots of good ideas here and I wish that this posting was available in August. I tried starting my early engine in late August after rebuilding it a few years ago and had no oil pressue. When I rebuilt the engine I filled the pump so that it would have oil immediately but I guess it had drained in the past few years! Anyway to make a long story a little shorter we pulled the little brass plus out of the middle of the banjo and filled with oil then turned on the starter and then topped it up again. We then fired it up and oil shot out of the hole like crazy. Once the plug had been replaced and the fender, floor and wall cleaned we restarted it and have had great oil pressure ever since.
|I also watched the Boyd Coddington episode with the oil pressure problem. He and his crew didn't seem too worried about running it with no oil pressure for short (but seemed like long) periods. Are modern engines somehow different when it comes to bearings etc.?|
From memory, after I change the oil/filter in the TD it takes maybe 4-5 seconds to get pressure after startup. With a relief valve change it took 5-7 seconds give or take. On a normal startup with no oil change it takes around 2-3 seconds (why I was changing relief valve..still the same by the way) to show pressure.
The next oil change I will certainly starter crank the engine until the pressure comes up, but do these short periods with little/no pressure do that much damage? How much shorter an engine life should I expect by just running it until pressure comes up? Thanks. Tim
|As a point for others. The thread on the brass plug above the oil pump on the early TD is a 10mm 1.50 pitch. At least that pitch and size will work in costructing a pipe that will fit the plug hole to put oil from the pump all the way to the lifters.|
This thread was discussed between 07/11/2004 and 09/11/2004
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