johnson 88spl new rebuild oil leak

[wt van metre]

I just rebuilt 1987 johnsson 88spl. Going throught engine break in with the double oil. Motor runs great.. i have unburned oil leaking for powerhead down the mid section. Its not that bad.. my question is is this normal during the double oil break in period. Thans for any help w.t.

 

[James R]

I have rebuilt many so I will try to help.What color is the oil and can you see where it is coming from. This is unusual.

 

[wt van metre]

The oil is green to . I dont think its the bottom crank seal. But is on top exhaust housing running down from the front long block bolt. Bone dry around fuel pump and carbs. Also have some oil on right hand side also. The split on the crankcase has a little on it. I did use loctite 518 and the primer when put it to gather.. motor runs great.. thanks for your help w.t.
.

 

[wt van metre]

Hey James i just looked it over with mirror. Question if it was comeing out of the outer side exhaust cover
What color would it b there .. looks like that might b my problem. Thers oil on the front side of the top exhaust cover. Right beside crankcase split. Be none on the split above the cover hight. So i dont think its the case. I just saw in the service manual that one of the exhaust cover are interchangeable and the lower starboard is different. Are they idiot proff or could i have them in the wrong place thas w.t.
.

 

[wt van metre]

What i meant to say in last post was three of the side exhaust cover r interchangeable and the lower starboard if different.

 

[Faztbullet]

Should not have oil itself leaking as a 88 has no VRO. Is the oil your mixing with fuel green and those are the intake covers. Does your have the recirculate line attaches to cover?

 

[racerone]

Those are not exhaust covers .---They are the intake " bypass covers "-----I would replace those 4 gaskets first, easy and cheap.

 

[wt van metre]

I premix no vro. Using quicksilver synthetic so the oil leaking color is greenish blue. Thanks for info.going to tighten them up i used avation gasket sealer on the intake by pass cover. If it is the crankcase what is exceptable amount of oil leak before i should split the case agian. Thaks w.t.

 

[wt van metre]

Hey fastbullet r u talking about the lines coming from intake to the bypass cover

 

[Faztbullet]

Hey fastbullet r u talking about the lines coming from intake to the bypass cover

Yep...one could be split blowing oil/fuel mix on the cover...

 

[wt van metre]

Thanks for all the info guys..

 

[James R]

Sorry I was unable to get back to you but the guys have a good handle on your problem.

 

[wt van metre]

Hey guys if its my crankcase split leaking what would b the acceptable amount for a leak. The oil is not burnt. Its Bluish green. I read on a post that said spray wd40 on the the split while running if it rev's up not acceptable thank again for your help w.t.

 

[jimmbo]

Zero

 

[racerone]

Have to ask.-----When you prepared the crankcase and cover did you clean all the old sealant off ?-----Did you carefully inspect and make sure that there were no burrs / imperfections on the surfaces ?-----Did you seat the center bearing on the dowel in the block ?

 

[rothfm]

I cant quite determine from the post, where you are seeing this "oil".

​But I had a similar unburnt fuel/oil mix greenish-blue that seeped out the front of the exhaust housing from under the powerhead, and ran down both sides of the housing.

​Was a real pain to figure out! Pulled the PH twice. Here's the scoop and something to look into:

​My issue was the 4 lower crank-head bolts that go into the retainer ring on the inside (not the 8 outside diameter bolts). On the 1st re-pull of the PH, I did the O-rings, and crank seals again. Remounted, and the issue still continued.

​Removing the Powerhead a 3rd time....I found that there are "seals" or mini O-rings under the heads of those 4 Lower crank head bolts. The OEM book is not clear about them. But on another motor, removing them showed signs of a seal material. And the surface under the bolt head is counter-sunk slightly to accommodate the.

​I then placed small O-rings around under those bolt heads, and not a drip since!!

​If you search, I had a thread with pictures if it can help.

 

[wt van metre]

Yes sir. After i had the cylinder bored 30 over i washed block in warn soapy water. Used razor blade to remove a the old gel seal. From mating surface and wiped it all down with acetone.. prime the surface with loctite primer and use loctite 518 gel . bearing is in correct place. If bearing was off the pin i wouldn't think it could go back together without binding i felt the bearing drop in.. it was real smooth to spinning the crank after put back together.. and it runs great. After running for 2.5 hrs flawlessly. The next day is when i noticed the oil it ran about 10in down mid section. Going to take it to the river tomorrow with some soapy water to see were leak is. See if i can get some bubbles. Thank you
W.t.
.

 

[wt van metre]

To rothfm.. on the bottom bearing plate bolts book calls to use new bolts which it did they had orings and i also used 518 loctite on them also.. my leak looks like it either the split on the case between 1 and 3 pistons or its the bypass cover. I also have some oil coming out the front like u explained but might have just ran down there . Going to run it tomorrow a see if i cant pin point were it comming form. . Thanks for your input w.t

 

[wt van metre]

Ok guys found one of my leaks. Very tiny leak.. its on the crankcase split between #1and #3 piston. I also have one on the bottom somewhere either crank seal or a bearing retainer bolt. I have split the case cleaned all surfaces with razor blade and acetone use straight edge to look for in perfection. And primed surface with loctite primer. Going to use 518 gel seal again.. and have change the bearing plat bolts. how much sealant should i use. Do i put it on both half's . And what is the tq. On the big hex bolts. Thanks for any tips or info w.t.

 

[rothfm]

I can get the torques a bit later from my OEM manuals....but primer goes on one side and the sealer on the other. I Forget which the manual calls for, its specific but I dont remember. I"ve always followed the manual and never had any issue. The Torques are important, and specified in the manual which you should have for the rebuild.

As far as sealer...I do a section at a time so I"m not working too large an area. I apply a small 1/8 bead around the flanges, staying 1/4" away from the journals and crank areas. Then spread and smooth with a finger. You just want a small layer. Not too thick, not too thin.

Make sure you use o-rings or some sort of seal below the heads of those 4 bearing retainer plate bolts on the bottom.