DLS BA Cranks Seal Knurling ??

[m233roller]

Ok, who can tell me if theyv'e had any rear main seal leaking problems with DLS's BA cranks with NO seal knurling done to them ?? Thanks Mike

 

[ttypewhite]

Hey Mike, Dan put together my Staged motor with the DLS/BA rotating assembly and I have put it through the paces and still no leaks on my garage floor.

 

[SNOWBIRD]

The problem was on the 109 stroker kits using a non knurled crank.BA CRANK. DO A SEARCH USEING KNURLING ,,,KNURLED CRANK ,,,,,,REAR MAIN SEAL LEAK and you will find some some info.

 

[Just a Six??]

The problem was on the 109 stroker kits using a non knurled crank.BA CRANK. DO A SEARCH USEING KNURLING ,,,KNURLED CRANK ,,,,,,REAR MAIN SEAL LEAK and you will find some some info.

I remember reading some threads about having leaks without the knurling maybe 1-2 years ago.

 

[SNOWBIRD]

ttype ,I assume your stage has a knurled rear main seal(chevy style) which the 109 does not ,this is why yours is not leaking ,i can go more into detail but i would like to hear from others first.

 

[ttypewhite]

That I can't answer, because my motor came assembled and I dropped it in the car, where it still is today. Sorry I couldn't be of more help.

 

[turbobitt]

Not sure where your going with this but here is my 2 cents. The knurl is really only designed to interface with the factory rope seal. Like any rope seal, they require some lubricating or they will burn. The wax or graphite impregnated in the rope will only serve so long without some supplimental lube. The new style retro-fit rubber or flourelastomer seals don't require a knurl to seal or survive against the crank. These seals are also very sensative to rear cap and block alignment since there is only a pinpoint area of contact. The two seal halfs must line up perfectly for them to work properly. The factory rope seal has a much wider/flatter contact area and wasn't as critical to have the perfect alignment.
Anorther factor in proper venting of pressure between the slinger and seal. Some aftermarket pans can block this venting and cause the seal to see oil pressure and leak.
There are a lot of other oportunities for the oil to leak from and give the impression that its the rear seal. For example, the mating areas of the cap to block should have something there to create a seal. The side seals also can be tricky.
FWIW, my crower crank has no knurl and seals perfect.

Allan G.

 

[KWIKR 1]

Out of Buicks now . But I went thru it with my stroker and BA Crank . Drove me friggin nuts !!!!!!! even went to the extend of contacting companys to come up or make a new seal that would remedy the problem .and I looked into other alternatives as well . The only problem was it would cost alot of $$$ to design it and put it into production . From my understanding seal on a SBC has a knurl in it that's why it can be used on a non knurled crank . Where the Buick rear main does not .look at post #18 you can actually see the knurl in the seal . I ended up spending $125 and getting the crank knurled . I sold the engine before knowing if it solved the problem . But ...I would think it did . Had many people contact me on this subject after they came across my posts .

http://www.turbobuick.com/forums/engine-tech/250048-ptfe-rear-main-seals.html

http://www.turbobuick.com/forums/engine-tech/250048-ptfe-rear-main-seals.html

http://www.signalseals.com/about_us.html this is the company I contacted about coming up with a knurled seal for Buick V6's .

 

[LOT]

????

My crower crank has no knurl and seals perfect.

Allan G.[/QUOTE]

Is this in a Stage II engine? If so does it take a BBC seal? How many miles?

 

[SNOWBIRD]

Thank you kwick ,paging LEE THOMPSON and any body else that has had this problem on a (109 BA STROKER CRANK) NOT A STAGE MOTOR WITH KNURLED SEAL

 

[m233roller]

Sorry guys,
I should have been alittle more pacific. This is for a 109 block, stock stroke DLS BA crank. I know about the Stage 11 stuff.

 

[SNOWBIRD]

stock stroke or stroker 109 it still needs to be knurled..hate to sink your ship,,,,,I burnt out 4 rear main seal kits (Overheated)due to lack of lines machined on surface of crank where seal rides....these lines hold some oil for lubrication and also due to angle of lines pitch oil back in towards motor.

 

[bad V6]

Just a question, but if the knurling was not needed on the crank of a 109 engine, then why did GM put it on the stock crank in the first place? If it only needed a better rear seal, I would think that it would have been cheaper for GM to have a different seal manufactured than the machine work on the stock crank.

By the way, my engine built by Weber has knurling on the stroker crank.

 

[KWIKR 1]

Sorry guys,
I should have been alittle more pacific. This is for a 109 block, stock stroke DLS BA crank. I know about the Stage 11 stuff.

Mine was a 109 block as well .

 

[KWIKR 1]

Just a question, but if the knurling was not needed on the crank of a 109 engine, then why did GM put it on the stock crank in the first place? If it only needed a better rear seal, I would think that it would have been cheaper for GM to have a different seal manufactured than the machine work on the stock crank.

By the way, my engine built by Weber has knurling on the stroker crank.

Because the original seals were a "rope" type seal .

 

[SNOWBIRD]

25 years ago gm only had rope seals at least thats what i remember when repairing oil leaks on warranty...........weber must be useing CAT cranks,my buddy bought a cat stroker kit and the knurl was so aggressive ,i was worried it would damage the rubber seal ........3 seasons of weekly 1/8 mile 25 psi blasts and it is not even wet ...O we do run a ele vacuum pump when boost comes in .

 

[LOT]

Mike

I assume you have thought about seeing if Weber would knurl it.

 

[turbofabricator]

I have used both types of cranks. Both work fine. If a Buick doesn't leak oil.........BETTER ADD SOME FAST!!!!!! Seriously though, the knurls were used on the factory cranks to allow oil to reach the rope seal and not burn it up. The aftermarket neoprene seals don't need the oil quantity the the rope seals do. The front hub (balancer) on a Buick is knurled, too, but the factory front seal is also a rope seal. (A carry over from the 1930's.) Rope seals work........they just don't work GOOD.

 

[Eticket]

If you follow those links... You'll find my solution to the problem. You don't even have to pull the engine to fix it.

 

[J-B Racing]

stock stroke or stroker 109 it still needs to be knurled..hate to sink your ship,,,,,I burnt out 4 rear main seal kits (Overheated)due to lack of lines machined on surface of crank where seal rides....these lines hold some oil for lubrication and also due to angle of lines pitch oil back in towards motor.

Thank God you fixed your problem Bob. You were losing sleep because of this...