I bought a 1993 Bronco, The owner told me that it has a stuck valve, How can I test for this and is it worth repairing or replacing the engine, I have found a junk yard motor for $300 with a 30 day replacement warranty.

PS: I have tried tuning it up and think the old owner had the wrong firing order but could have been my fault, there is a lot of exhaust smoke coming out of the breather.

 

First question... "Breather"? The only location where the crankcase is open to the atmosphere in that model year is UNDER the air filter INSIDE the filter box. If there is exhaust coming from the crankcase you have problems far more serious than a stuck valve.

To test for a stuck valve you will need to perform a compression test on each cylinder to determine which cylinder is affected. Compression in a cylinder with a valve stuck open will be zero. A valve stuck open usually has tell-tale rhythmic chatter unless it is stuck just slightly open and the top of the piston doesn't smack it as it reaches TDC. Still, if a valve is open there will be some noise from the rattling of the pushrod and rocker arm for that valve. A valve stuck closed will either bend or break a pushrod or rocker arm. Either will yield obvious noise from the engine.

 

if the valve was stuck the motor would have a tick or knock going on. is the engine making any noises?

what does the oil look like?

 

They oil was dirty but good we currently are flushing the oil.

 

There's decently a smoke and or steam coming out of the breather and it smells like exhaust

 

what about the noise??? you havent answered that question.

is the oil milky or discolored at all? its possible that you have a blown headgasket if there is no noise.

I would drain the oil, put in a delo or rotella diesal grade oil 15w40. install a motorcraft, wix, purolator oil filter and run the motor. I would also recommend installing a new pcv valve which should be located on the passenger side valve cover in the back.

 

I think that doing the engine flush fixed the problem but we where testing it out lastnight and before the 4x4 would not turn on and last night we where driving and it turned on also it dropped its tranny fluid I'm not sure if its going into

 

#1 no engine noise
#2 There was some milkyness on the cap but not on the dip stick - I think this is do to the truck sitting for a few months and condensation build up (hoping)
#3 changed the oil using an engine flush - used Mobil 5000 and a Purolator filter, have not changed the PVC valve - will do that today

Thank you for all the help so far

 

Breather is no longer smoking, flushed the radiator 3 times its looking good. Engine is running good.

Thanks for everyone help

 

You didn't find the cause yet, you better take a harder look into it, because it will come back, I would seafoam that engine to clean it further, do a search for seafoam and seafoaming.

 

Thanks for the reply, I both seafoamed the crank and fuel yesterday,

 

Now just drive the heck out of it

 

Did he answer the question...???