Engine/Transmission (1994 - 1998) Question: Excess Crankcase Pressure?

[RGoglin]

Help! Just completed a re-power of my dad's motor home, Chevy 6. 5 out CTD 5. 9 in. Transplant engine is from a 94-5spd pick-up with 80,000 miles. Question I have is: What may be causing oil to be forced up and out of the dipstick tube? Seems to me that there is too much pressure in the crankcase. Vent hose appears to be venting without obstruction. Otherwise engine runs well and makes good power, there doesn't appear to be any other problems. Any info would be appreciated.



Thanks,

Russ

 

[BPonci]

check crankcase vent very close. it is possible you need to run a slack tube manometer test.

 

[illflem]

Most times excess crankcase pressure comes from boost slipping past worn piston rings.

Make sure the vent tube is truely wide open it's entire length.

 

[RGoglin]

Thanks for the info guys. I will check things out a little closer and let you all know what I find. I hope it is vent tube obstruction and not worn rings!

Russ

 

[Reb.B]

well it could be plugged vent in the rear of the engine on the drivers side, but it could also be a worn engine. Even if its worn a little, it can still make good power. What i did on one engine was put the vent tube from a 24v and put it on a 12v. The 24v vent hooks up in the front case cover, in front of the injection pump. to add oil u need a industrial front valve cover with the oil plug, or just pull the hose off the front vent and pour in. Works great, no more oil blowing out all over, good luck.