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MG MGA - #11 Cylinder Head Stud/Dripping Oil/High Oil Press
It's been several years since I posted here and the last questions I asked were about what type of head gasket to use. Back then no username or password was required, which was much nicer than having to remember another password. Anyhow, I wish I could be asking more questions like "My tires are worn out, what brand should I get now," or "What type of motor oil are you using?" etc. but alas I broke the car about 2 or 3 years ago retightening the head studs (maybe I did post some questions on it now that my brain cells are being used) at the 500 mile mark. I have exhausted every opportunity I had being able to drill a hole into the center of the broken stud and using a screw extractor. At this point there is very little remaining in the hole and I do not have enough material to get what remains of the broken stud out. First off, let me clarify this is the #11 head stud on the back of the engine block (rear of the engine bay right atop the transmission bellhousing). I actually drilled straight through the engine block (underneath the head stud hole) on a couple occasions. I was wondering if underneath that #11 head stud hole, is there an oil or water passage that I have compromised? Second question on this topic is what would you be looking for a machinist to do in order to repair this damage? Helicoil or is there another better product out there? Maybe there is a more generic rethreading process that can be done? Is it possible/recommended that I use a propane torch and try to heat up the remaining bits of drilled out head stud and see if I can't pop them out? Next question is assuming that I pull the motor (2nd time in 500 miles; cursed head studs/torque wrench), I had two issues after our fresh rebuild. First off was that the oil pressure would read between 60-80 PSI at idle no matter what temperature the motor was at. Everyone on this forum agreed that this was a bit high considering 20 PSI was about what everyone else would run at idle, but if I tear this motor apart, what do I look for/repair to relieve some of this high pressure? Last question, which might be related to the high oil pressure and keeping in mind that I know there is only an oil slinger, not seal, at the rear of the crankshaft, is it possible to keep that junction from dripping oil? If not, what I would assume is that from the factory these cars leaked oil out of the tranny bell housing where the cotter pinned hole is. I would love to know how to keep the love slick of oil to nil if at all possible from that rear oil slinger. I know this was long, but please understand I value each and every peson's input even if it's only their "gut" feeling and not based off of any first-hand knowledge!!! Cheers! -Jamie |
J DeRienzo |
Jamie, Maybe try a left hand drill bit - these are available in 0.5mm increments and try in conjunction with a Starret type screw remover (doesn't expand the stud like an Easi-Out). Mike |
Mike Ellsmore |
Jamie, Don't give up! The guys on this forum will get you through any problem. There is nothing that cannot be fixed! If you can post pictures it helps a lot. In the mean-time (when waiting for replies and for interest) spend some time on Barneys site mgaguru.com and don't forget to browse around his links to other great sites. That should rekindle the passion! If you save the page after sign in you don't need to use your password each time. This was introduced after some unwanted spam. I will have a look at a spare engine block to see if I have anything useful to comment. Good luck, Neil |
Neil McGurk |
To remove the stud get a magnetic drill press so that you will drll a straight hole. Set it on top of the block and drill the broken stud out to a size just under the inner diameter of the thread. You will then be able to peel the remaining stud out of the thread. If the present hole is off cenetr you will need to use a end mill in the drill press in place of a drill bit. The safe bet is to take the block to a machine shop and have them do it. High oil pressure may be caused by the oil pressure relief valve being stuck closed or a restriction some where in the oil passages. Spun main or rod bearings can also increase pressure. |
J Heisenfeldt |
My engine also runs with 60-80lbs pressure till it warms up, then drops to running at around 30-40lbs at idle, 60-80 at speed. Did you remove the head completely, or is the head still on the car? |
dominic clancy |
My oil pressure stayed at about 80 psi pretty much regardless of temp. I will obviously be removing everything out of the block for the machinists to do my helicoil and resurface the block and cylinder head. The head was removed as soon as I snapped the head stud. I will be taking a look at the crank and the bearings to see if there is any sign of damage that would cause the high oil pressure. Any ideas from anyone as to keeping the motor from leaking oil once together??? |
J DeRienzo |
Rear oil seal conversion? Here's why it might leak: http://mgaguru.com/mgtech/engine/cs109.htm And here's a way to fix it!!! http://mgaguru.com/mgtech/engine/cs202a.htm Neil |
Neil McGurk |
This thread was discussed between 15/01/2008 and 16/01/2008
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