Lou64

64 with Muncie. Engine has less than 100 miles on it. It's blowing a lot of white smoke out of the right side (passenger) pipe only and really only noticeable at throttle liftoff with clutch out. No distinct smells. My side pipe on that side has some soot after only driving home from the shop. Last time I drove it it overheated and boiled coolant.

A quick internet search revealed it could be head gasket, intake gasket, or even cracked block. Any ideas on diagnosis of which it is?

claysmoker

New engine? Bet it's a head gasket.

Pop Chevy

Yep. Start with a compression check.

phil2302

Was it a short block that you dressed with your carb?
Check plugs on that side if black and sooty could a a too rich situation.

GCD1962

White Smoke - Coolant

Lou64

Revised original post to mention that it is only noticeable when lifting off the throttle with clutch out.

Lou64

It is a 290 horse long block with a Edelbrock Thunder series 4 barrel (much like a Carter-2 mains and 2 secondaries)

phil2302

White steam would indicate it is coolant.
Feels wet on the hand.
If it is actually white smoke and not steam its may be an overly rich air fuel mix.
First check for black sooty plugs.

out2kayak

Before you get too deep into testing stuff, take a look at your engine oil. If it looks like mayonnaise (on the dipstick, oil fill, etc.), it has water mixed with it and ought to be changed before rotating the engine.

Take a look at your coolant level -- is it in the normal range or is some missing after you refilled it from overheating? Again, this may be a sign of loss. There are coolant testers for combustion (something like http://www.nationaltoolwarehouse.com...or-P58326.aspx).

What does your spark plugs look like? Does one or more look steam cleaned compared to the others? In other words, are several spark plugs brown and one or more clean? Coolant leaking into the cylinder will wash the spark plug clean.

If the above are OK, then I'd check compression.

FWIW, it is possible to leak coolant without it showing on a compression test, yet still be burned in the combustion process (like a head crack or a bolt / manifold / etc. leaking coolant).

FWIW. YMMV.



-- Joe

Kerrmudgeon

If it's a crate motor it should be under warranty. Just call and have it replaced....don't mess with it. Start fresh.

Westlotorn

If it was overheated warranty is not valid.
White smoke is coolant. Sorry.
Did it smoke before your overheat?
When you overheat the head will expand and crush your head gasket in the hot areas.
You can measure the crush with a mic. You also usually find the head bolts loose around the crush. If the heads are not damaged new gaskets fix you right up.
Why did it overheat? You don't want to fix it a third time so best to fix the problem before the new start up.
Any engine shop will check for overheat on a warranty tear down, you can't hide the evidence.

sub006

Mayonnaise? When my daughter's faithful 300,000 original mile '84 BMW started blowing white smoke I thought "head gasket". Pulled the dipstick, looked like peanut butter clinging to it. Maybe different coolant and oil brands affect the color?

Crunch527

That engine is too cheap to pay the money to open up...agree with "warranty swap" and move on...maybe get something with a little more oomph since you are there anyway...

maroon67

Coolant being burned usually gives the exhaust a sweet smell as well as white smoke.

65tripleblack

Who installed the intake manifold?

If it only "smokes" on the coast, clutch engaged, then it might be sucking it into an intake port from a crossover coolant port in the intake during high vacuum periods.

GTOguy

^^^This. Sucking coolant on high vacuum situations. If engine oil is clean, probably an intake issue. And, no, white smoke is NEVER an indicator of a rich fuel air mixture. Not on this planet, anyway!

Lou64

Looks like #6 took a dump...I will be looking into warranty I suppose.

Westlotorn

Plug looks more like carbon fouling, you sure your smoke is not blue?
#6 could just be a valve stem seal or intake gasket issue. Much easier change than installing a new engine.
What caused your overheat and how hot did it get?

Lou64

It looks more like metal shavings to me, and if you look closely the base is covered with oil too.

GCD1962

Don't know if the crate engines have it, but some rebuilders put a heat disk on the block. If it overheats the disk indicates it and the warranty if void.