SwedeSpeed - Volvo Performance Forum banner

1 - 5 of 5 Posts

·
Registered
Joined
·
314 Posts
Discussion Starter · #1 ·
Anyone have a solution for keeping the B18/B20 rear mainseal from leaking? I just installed a brand new one in my 3/4-race-prepped B18 (bored out to B20 spec, big valves, high-lift Isky cam with lobes the size of your elbow, extensive headwork, etc. etc. etc. - roughly 165HP @ flywheel) street motor (daily driver) and of course the engine sees 7,200RPM shifts (was designed for it). Yet, the higher the revs, the more likely the seal will fail, as it has done in less than 500 miles of driving since installing the damn seal! <IMG NAME="icon" SRC="http://********************/smile/emthdown.gif" BORDER="0"> I am looking for a solution for this incredibly crappy design so that I am not always topping off the oil level every week. Has anyone overcome this weak link? Thanks.<p>-he who stacks pork
 

·
Registered
Joined
·
314 Posts
Discussion Starter · #2 ·
Re: B18/B20 rear mainseal - sucks! (Leopold Porkstacker)

OK, this morning I spoke to the Swiss fabrication specialist who is to be turning my 122SS into a Volvette (I learned as per our conversation that the track is 4" wider overall than the Volvo, and the wheelbase is only 1" longer!!! this is good news!!!) that the engines he builds for his NASCAR racecars have a special crankshaft which has a sort of inward spiral sort of like a screw thread setup which is located just in a bit from where the rear mainseal goes. What this does is draw the oil away from the end of the crankshaft. Apparently this is really expensive to have done though, since it really requires the crank to be machined on a special type of gear-making machine. And from what I've read, making gears is ultra expensive.<p>So, short of having a multi-thousand-dollar crankshaft (may as well stroke it while we're at it!) in the Volvo engine, can anyone come up with an idea other than that or replacing the rear mainseal ever 500 miles?<p>-he who stacks pork
 

·
Registered
Joined
·
314 Posts
Discussion Starter · #3 ·
Re: B18/B20 rear mainseal - sucks! (Leopold Porkstacker)

Well, after asking a guy who works for a Volvo salvage shop/parts business about the rear mainseal leakage issue, he suggested popping an o-ring onto the inside of the seal where the crank end comes out. The idea being that the o-ring provides enough tension so as to sort of grip the seal and bring it closer to the crank end. I'll have to try this sometime soon, as the 7,200RPM shifts are claiming lots of oil; I need to top the damn thing off regularly!<p>-he who stacks pork
 

·
Registered
Joined
·
342 Posts
Re: B18/B20 rear mainseal - sucks! (Leopold Porkstacker)

This might be a silly question, but is the engine balanced? The standard B18/B20 crank has some pretty heavy couterweights on it. I would imagine that 5000+ RPM would be hard on the crank seals if the moving parts weren't balanced.<br>
 

·
Registered
Joined
·
314 Posts
Discussion Starter · #5 ·
Re: B18/B20 rear mainseal - sucks! (Elwood)

Yes, everything was balanced when the engine was built, hence the recommended shift RPM range of 7,000+.<p>-he who stacks pork
 
1 - 5 of 5 Posts
Top