How to tell if an engine needs overhaul, before going to the shop?

www.polarislabs.com

 

LessThan 3 to 4000 miles to a gallon of oil then I'd consider a overhaul otherwise just run it.. Your motor sounds like it's still healthy to me.. Get a shop to check bull gear and maybe change harmonic dampener rubber fuel lines if they are factory and you should be good a few years I'd think

 

I agree with the poster that said you put it on a dyno and sending oil to a lab. Then I would go from there. Good luck and let us know what the results are.

KH

 

Take the truck to the hills with 45 000 lbs and watch the temp. on the water, if the needle never goes to 225, you have a good motor.

 

Checking the crankshaft end play will also help give you an idea what the future holds in store for them bearings. Sounds like the top end is pretty good.

 

I got 1.2 million miles from mine before it started to drink coolant! Sounds like your motor is healthy as day one! Drop the oil pan and check the bearings! Always remember never to throw money at a motor, only when it demands it!

 

a gallon to 2k miles is the best guestimate. blowby and a good (polaris) oil analysis done regulary will keep you informed. Dont use Speedco, no calibration, just a sales tool for upgrades.

 

I use black stone labs. I would recommend the following:

Run oil sample. Get results and check them against the averages on that series of motor
If that's good put it on a dyno and have a blow by test done. Detroits have a lot but there is a average line on that series of motor.
If you know nothing about the motor an the two above are good, put main an rod bearings in it along with a harmonic balancer.
At the end drive it like you stole it.

Mine has 950k on it use less than a gallon of oil between changes doesn't smoke an passed all the test with flying colors. Most the results on oil sample where better than the averages. You will spin a bearing or blow a head gasket before a major catastrophic failure of a rod or ring, liner or block. Bearings are cheap an easy to replace and can save you in the long run.