Engine problem - possibly time to replace
Thread Starter
Racer
Joined: Oct 2011
Posts: 495
Likes: 23
From: Killeen, Texas
Engine problem - possibly time to replace
I took the 454 out for a drive this afternoon. First I noticed a little hesitation upon acceleration. I didn't think much of it because the engine was cold. I pull off the highway after about 45 minutes of driving and at the first red light I notice my temp gauge at 210 when it never goes over 180. I also notice the oil pressure gauge is pegged at 70, it's usually around 35-40. I pull over, lift the hood and see milky oil seeping out of the pcv valve opening and the oil cap. I pull the dipstick and of course it's milky too.
Obviously coolant has made it's way onto the oil but at least I don't have any white smoke from the tailpipes as I thought I would have.
I had it towed home and now I need help. Based on the above do you think I have a blown head gasket, cracked blocked, or something else?
I don't know much about the engine other than it was advertised as a NOM and has Edelbrock heads.
Obviously coolant has made it's way onto the oil but at least I don't have any white smoke from the tailpipes as I thought I would have.
I had it towed home and now I need help. Based on the above do you think I have a blown head gasket, cracked blocked, or something else?
I don't know much about the engine other than it was advertised as a NOM and has Edelbrock heads.
Racer
Joined: Sep 2011
Posts: 414
Likes: 55
From: Humboldt county Ca
Don't know nothin' 'bout 'nothin, especially big blocks but my money would be on a head gasket. Possibly a blown intake gasket. Either way, you will need to pull the intake to get to the heads. Sounds like a lot of coolant went into the oil if that's what jacked the pressure up. Probably time to start dragging out the wrenches!
Let us know what you find.
I'm crossing my fingers for you.
Stump
Let us know what you find.
I'm crossing my fingers for you.
Stump
Le Mans Master
Joined: Dec 2006
Posts: 8,837
Likes: 1,027
If you got enough coolant in the sump to change oil pressure, that mud was pumped all over the place. Since mud does not lubricate well, and you need to clear it all out and solve the issue, I would take it out and have it rebuilt. The bearings turn to crap real quick. The sooner, the better chance of saving what you have. My 2 cents.
Racer
Joined: Sep 2011
Posts: 414
Likes: 55
From: Humboldt county Ca
Back in the late 60's I had a 305 that was notorious for blowing head gaskets and dumping water in the pan. I first re torqued the heads, hoping to get lucky, but never did. After checking the bolts I drained all the oil and coolant and changed the gaskets. By that time a day had gone by with water in the oil. With the new gaskets in, I put the cheapest 30 wt oil in I could find, put in coolant and ran the engine up to almost overheat with cardboard over the radiator to try and boil the water out of the internals. That rig ran another 10 years without any bottom end damage after having water in the pan at least 3 times.
just my experiences with small blocks.
Stump
just my experiences with small blocks.
Stump
Burning Brakes
Joined: Jan 2003
Posts: 961
Likes: 275
From: Frederick MD
I took the 454 out for a drive this afternoon. First I noticed a little hesitation upon acceleration. I didn't think much of it because the engine was cold. I pull off the highway after about 45 minutes of driving and at the first red light I notice my temp gauge at 210 when it never goes over 180. I also notice the oil pressure gauge is pegged at 70, it's usually around 35-40. I pull over, lift the hood and see milky oil seeping out of the pcv valve opening and the oil cap. I pull the dipstick and of course it's milky too.
Obviously coolant has made it's way onto the oil but at least I don't have any white smoke from the tailpipes as I thought I would have.
I had it towed home and now I need help. Based on the above do you think I have a blown head gasket, cracked blocked, or something else?
I don't know much about the engine other than it was advertised as a NOM and has Edelbrock heads.
Obviously coolant has made it's way onto the oil but at least I don't have any white smoke from the tailpipes as I thought I would have.
I had it towed home and now I need help. Based on the above do you think I have a blown head gasket, cracked blocked, or something else?
I don't know much about the engine other than it was advertised as a NOM and has Edelbrock heads.
If the filter is clean pull your plugs and see if coolant is in the combustion chambers. Look at your plugs. Are they steam cleaned? Also do a quick compression test with the plugs out. If everything checks out ok then I’d bet on it being an intake leak and not a head gasket. Still could be a head but now you can be reasonably certain. If there is a head gasket issue there is obviously alittle more work involved but as long as the motor didnt start munching itself, and you can get the slurry mostly out it shouldn't need to totally come out.
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Race Director
Joined: Jul 2015
Posts: 13,082
Likes: 3,398
From: SW Florida.
this looks like related threads strikes again. 383 admiral wasn't saying anything about this 454 issue. was talking about 94 opti-soark LT1's.
Last edited by derekderek; Aug 31, 2022 at 05:28 PM.