my 1997 e-150 van with 4.2 v6 and 110,000 miles has been running rough for a few seconds at start. but fine after that. at first I thought it was an injector and used a good cleaner. I have lost a bit of fluid. now smelling antifreze. i was told I may have a cracked head rather than just a gasket cause it doesnt get worse. I also talked to another person that replaced 2 NEW heads with bolts on a 4.2 and had same problem within 4000 miles. is there a problem with 4.2 engines and any suggestions on repair or what to pay attention to. jeff

 

IMO you can't discount the "problem" of running a 4.2 V6 in a 5000 lb truck-its a hard job-can mean an excess number of hours at full throttle. You must confirm where your "antifreze" is going. Look for white smoke out the exhaust when you blip throttle, check if water in exhaust is source of what you're "smelling" & not a sneaky external leak. Check for drips by parking on a 'clean slate' overnight & look for spots. Pull the spark plugs & check to see which plug(s) get wet. Some cracks can be seen, thru spark plug hole, using mechanic's special optical tools. Cracking heads/blowing head gaskets can go the other way, admitting combustion gases into the water jacket & displacing coolant, ultimately overheating-check for overflow & contamination.

I'm sure you're aware there's quick'n'dirty leak cures galore & lots of experts who recommend against them. Fact is many people do recommend the stuff & have good luck with it. There are just so many different situations, its always a gamble when you pick one. Think of it as temporary-last resort-test for under $10 that you can do in the next hour & keep driving. You know the alternative-major off road surgery in order to even learn how costly.

 

If you have a cracked head that is venting coolant into a cylinder you will also be able to see compression in the water jacket. With the engine warm, top up the coolant and run the engine with the radiator cap off and watch for bubbles in the coolant. If you have bubbles, you are venting compression into the water jacket. It could also be a blown head gasket but you would have to pull the heads either way.

If you are getting coolant into a cylinder you will be able to see which cylinder by looking for a clean spark plug.

If you don't see compression in the water jacket and no coolant leaks and evidence of water in a cylinder or two, then its likely a blown intake manifold gasket. Start with the manifold and work your way to the heads. With the heads off a good machine shop can check them for cracks.

Steve
'95 Clubwagon XLT

 

thanks for the info. I remember the bubbles on the gm diesels back in the 80 but forgot all about checking. im going by what a mechanic said when he looked at it. the van sits outside on gravel and i couldnt smell anything before. intake would be sweet, I hope so. thanks for the advice