1650 Gas

cstrucks · Sep 29, 2023

I have a 1650 gas that is smoking blue smoke and using oil pretty bad. The engine was supposed to have been rebuilt a couple
years ago. Any ideas on what to look for. I know rings and valves could cause this but it ran great for 2 plus years and then
started the smoking and using oil.

super99 · Sep 29, 2023

I'd start with a compression test

Dieseltech · Sep 29, 2023

Check out the air cleaner system, ANY air leaks on the clean side connections to the carb, OR the wrong length air filter if dry type will allow dust to enter the engine quickly wearing the rings and sleeves.

rrlund · Sep 29, 2023

Could be they just didn't break it in right. Hook it on to a feed grinder or something and work the snot out of it.

rustred · Sep 29, 2023

first think is to pull out the spark plugs and examine them to see whats happening it might be one cylinder's fault, to see it oil smoking is not good. something going on there. broken rings cracked piston ?? see if one plug is more oil fouled or are they all the same. then check the compression. then post it. 5 puff's from each cylinder with throttle opened and a good battery. plus how much oil u using in what time frame?? give details. i have a 1755 that will go through a gallon a day but it dont smoke.

Gary Mitchell · Sep 29, 2023

#1 compression check.
#2 valve seals.
gm

oliver90owner · Sep 29, 2023

Or it has been run on a fight light load for long periods. Same cure.

Checking plugs first might be better than loading it heavily, before finding one cylinder gives out big time.

John Deere had problems with high oil consumption on new tractors - not run-in under a sufficient load. Rumoured that one dealership cure was to feed the engine with a scouring product (Vim?) and then run it in properly.

It is why running-in oils are often used for the first service period.

Fully synthetic lubricants can prevent proper bedding-in of rings, too. Just too slippery.!

Tramway Guy · Sep 30, 2023

not run-in under a sufficient load. Rumoured that one dealership cure was to feed the engine with a scouring product (Vim?) and then run it in properly.

I was told that some use Bon-Ami

rustred · Sep 30, 2023

it has been running for 2 years he says and now just started smoking,... so if thats the case its nothing to do with break in procedures now. if its smoking there is a problem to look into by checking the plugs first thing. yes bon ami was used for break in on new rebuilds and i have done it.

atex57 · Oct 1, 2023

Our 1650 was using oil badly over the years even without being used that much.Switched from gas engine oil to 15W40 diesel oil reduced the consumption.

Olliejunkie · Oct 2, 2023

Is the breather plugged. Does it blow smoke out the oil fill. Air cleaner clean. Does it have a oil bath air cleaner.

out to pasture · Oct 3, 2023

I know you posted several day ago
1 check air breather 2 check crank case ventilation tube 3 keep it simple plugs will tell you a lot on an old gas engine.
If fuel or water or engine oil are not exchange with each other will be another tell tell sign
Check simple things first they will.lead you in correct direction most always
another step would be check see if your getting bubbles in radiator. when it is running

This post was edited by out to pasture on 10/03/2023 at 06:18 pm.

cstrucks · Oct 12, 2023

Update on the 1650, compression test showed 140-150 PSI on all 6 cylinders. leak down test failed bad on all cylinders, I could hear air escaping into crankcase with dip stick removed, so I have tore engine down and found that compression rings looked good but oil rings looked like they were below the piston ring surface, the head was also warped and valve seals looked like engine had been hot. Also found that the air filter was orginal and very dirty. So shes getting new sleeves , pisons and rings, bearings seemed fine and was holding good oil pressure. Crazy how it had that good of a compression but failed so bad on leak down. Thanks for your thoughts on this

J.Wondergem · Oct 13, 2023

If it gets run hot enough, the first thing that will go is the oil rings.

scootergmc · Oct 13, 2023

Yes, sounds like it was run hot. You're rebuilding the head, etc. too, correct? How was the deck?

cstrucks · Oct 13, 2023

Yes head was checked and was out .008-.009, new seals were installed and checked for cracks.

1650 Gas

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