Oil leaking through oil pan bolts

[Guest]

My son purchased a 1982 GS 750 E, previous owner got it as an assembly project, replaced 3 rods, and crank, reassembled with all new gaskets. About 200 miles now after purchase, leaks oil through the oil pan(?) bolts.

Suggestions on how to stop the very slow drips will be appreciated.

Thanks

[tkent02]

Retorque the bolts?

[fastbysuzuki]

Maybe the fasteners are not tight enough or the po has used a copy/homemade gasket that is no up to the job in which case drop the oil clean the surfaces thourerly and get a Suzuki gasket and refit to the correct torque and fill with oil.

[Brendan W]

Take them out one at a time and clean under the flange on the head and on the pan and torque them to whatever the manual says. I think there should be 18 of them and they should be 25mm long. Overlong and they will bottom out. The holes generally will accept a few mm more so this is really only and issue if some are 30mm long.
Pans can warp. Are you certain it is the pan screws and not running down from a sidecover, the mystery hole in the starter motor cavity or the gear shift shaft.
Is it possible that a few have damaged threads and you can't get the required torque ?
Last resort would be a sealer on the gasket but that shouldn't be required if everything else is good.

[tkent02]

Bolts could also be too tight, which will smash the gasket around the bolt holes and make them leak. Did the guy that put the engine together know what he was doing?

[Crockett]

Claimed to be a master motorcycle mechanic, shop looked clean. He gave me his business card and asked me to share his information. The shop, discussion, and fact he gave me his card gave me some comfort. But heck, I could claim to be a master motorcycle mechanic. Time will tell.

[Crockett]

Definitely leaking from the front two pan bolts nearest to the oil filter cover. There is a leak behind the sprocket cover but only leaks when the bike is on the center stand. I have twins, one has a 85 V65 Magna and the other 1982 GS 750. They are learning but dad has most of the wrench duties so far. I will pull the bolts, check the length and torque properly and see what happens.

thank you

[Crockett]

Thank you guys, I will let you know how it works out. Hopefully the po did not sell me a grenade.

[Nessism]

First thing is check to see if the bolts are tight. If not, snug them down. If they are, pull the pan and replace the gasket. OEM gaskets only if you value oil tightness.

Welcome to the world of 35 year old motorcycles. Jobs like this are routine and you should expect other similar issues to pop up on a semi regular basis. With proper maintenance the number of unexpected issues should be minimal. You might want to check the Newbie Mistakes thread linked in my signature for some key items to be aware of.

[geol]

Oil can't leak from pan bolts if the pan is not warped or the gasket is no compromised. Of course, some of the bolts may be loose but as many bolts as are on the pan gasket, it wouldn't leak if only one were loose.

If it were mine, I would buy two pan gaskets to be on the safe side and reinstall using both with gasket sealer. I buy gasket sealer from NAPA; it comes in a small can with a brush. Put it on the mating surface then the first gasket where it mates and stick them together then let them sit an hour then install the other gasket on the pan using the same sealer and technique and after lett both sit for a bit put the pan gasket on and install; loosely tightening the bolts. The next day, it is time to torque the bolts. Do not tighten adjacent bolts but work around in a patter where you tighten one then move to the other side and once all are snugged, use the torque wrench at about 110 in/lbs. Over tightening is a mistake and unless you are a very experienced mechanic, this is the tendency. If you do it this way, it won't ever leak and it will take care of a warped pan gasket or a mating surface that has been gouged when someone was cleaning it of an old gasket. I have seen folks clean old gaskets with a chisel... ouch.

[Nessism]

Oil can't leak from pan bolts if the pan is not warped or the gasket is no compromised. Of course, some of the bolts may be loose but as many bolts as are on the pan gasket, it wouldn't leak if only one were loose.

If it were mine, I would buy two pan gaskets to be on the safe side and reinstall using both with gasket sealer. I buy gasket sealer from NAPA; it comes in a small can with a brush. Put it on the mating surface then the first gasket where it mates and stick them together then let them sit an hour then install the other gasket on the pan using the same sealer and technique and after lett both sit for a bit put the pan gasket on and install; loosely tightening the bolts. The next day, it is time to torque the bolts. Do not tighten adjacent bolts but work around in a patter where you tighten one then move to the other side and once all are snugged, use the torque wrench at about 110 in/lbs. Over tightening is a mistake and unless you are a very experienced mechanic, this is the tendency. If you do it this way, it won't ever leak and it will take care of a warped pan gasket or a mating surface that has been gouged when someone was cleaning it of an old gasket. I have seen folks clean old gaskets with a chisel... ouch.

The factory torque spec for the oil pan screws is 54-78 in lbs. 110 in-lbs is way too much (double the spec).

One factory OEM gasket is all you need. Suzuki didn't use sealer on the gaskets and the engines didn't leak from new, but feel free to use sealer if that makes you feel better.

[Brendan W]

Definitely leaking from the front two pan bolts nearest to the oil filter cover.

That's a bit too much of a co-incidence for me. It has a weird serpentine o-ring seal that gets pinched easily going back and the cap nuts are routinely overtightened and strip the stud threads.

[tkent02]

The factory torque spec for the oil pan screws is 54-78 in lbs. 110 in-lbs is way too much (double the spec).

One factory OEM gasket is all you need. Suzuki didn't use sealer on the gaskets and the engines didn't leak from new, but feel free to use sealer if that makes you feel better.

110 will smash the gasket and make it leak. One Suzuki gasket, dry or sealed won't matter, use the proper torque spec...

[geol]

110 in/lbs is pretty normal for steel case cover bolts... my mistake. The double gasket and sealer solution was given to ensure that the job wouldn't have to be done twice in the event the cover was slightly warped or some had GOUGED the cover when removing an old gasket. What Suzuki did from the factory is not really relevant if these things happened at some time in the past and it doesn't matter what type gasket is used if there is a big gouge in the cover or if there is warpage. I do believe if the torque value is as stated (54-78 in lbs) by all means use that value.

The filter gasket suggestion should also be heeded and the leak could also be from a drain plug not sealing. Best thing to do probably before pulling the pan is to degrease the whole area and spray it with powder based deodorant to see where the leak really comes from. It may be walking to the low point which might APPEAR to be case bolts.