I own an 82 blazer diesel. when i got it it had been converted with a rebuilt gas engine 350 ci. i drove it from washington to alaska n only problem was a blown front seal on the trans. it was parked for 6 yrs then got it back on the road. i drove it 35 mi. an blew 3.5 quarts of oil out of what seams to be front seal on the timing chain cover. replaced the seal n it seems to still build up pressure inside the block and still blowing oil out. any one know what could be causing it. broken rings?

 

Valve guides or seals? Valve seals may have hardened up over the six years it sat.

 

my boss had this issue with his, he had a 350turbo tranny so when going down the highway rps were high, he was blowing the front seal all the time, we put two PCV valves and two valve cover breathers on it and it seemed to work alot better.
The root of the problem is probably bad rings causing blow-by

 

yeah see if the pcv valves are clogged. thats what vents the engine, if they are blocked up the pressure will increase inside the block.

 

Thanks for your info but the things that have been suggested have already been done. I put in the second pvc before this latest incident. i have also performed a compression test and there is no broken rings to suggest blow by.
think its time to pull the engine and tear it down and see if i can find it.
thanks