Oil for low compression engine?

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I have a Long 460 45HP Tractor. It has a 3 cyl Uzina Diesel Engine. It has low compression, tons of blow by, hard to start. It takes a squirt or two of starting fluid in front of the filter to start everytime unless it has a very full battery and it is very warm outside. When it is cold outside(35 and below) it is almost impossible to start even with starting fluid straight in to the intake without going through the filter.

Now to my question. Should I go with a heavier weight oil to try and keep more compression or go with a lighter weight oil so it will spin faster and start easier? If i do go with a lighter weight oil will it create worse compression issues?
 
Sounds like you need a new engine or a rebuild not advice on oil
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Originally Posted By: OVERKILL
Sounds like you need a new engine or a rebuild not advice on oil
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Ditto!

No oil is going to avoid the type problems you're indicating exist. Why not try each and see if there truly exists any benefit to either? Then tell us which worked for you, if it made any difference whatsoever. I suspect it would be marginal in assistance at best.


Welcome to the site, Austin!
 
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Austin,

Mystik JT-8 15w-50 is available at your local O'Reilly. Good luck -- report back and let us know how it goes.
 
What you have there is basically a Romanian U445 tractor that was sold long ago in US under the Long brand.

We have the same tractor and if you need any info on it just feel free to ask.

The parts for a complete engine rebuild here are about $300 and doing it yourself is a piece of cake
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Please post pictures if you have them
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I forgot to mention that sometimes the centrifugal injection pump takes a dump or it effs up the injection timing making the starting a nightmare and the tractor has no life when under load.
 
If i can give some cheap advice. I had a similar problem in a powerstroke diesel..it was worn out.. hard to start and blowby.. an old timer told me to fill the fuel filter full of howes meaner cleaner.. fire it up and then shut down let that meaner cleaner soak overnight in the fuel system and injectors..then pour the rest of the bottle in the fuel and start it up the next day..then run it like u stole it (italian tune up).

In my situation it seemed to give the truck more power and was a whole lot easier to start.. maybe a fluke but it worked.

Those old timers also swear by straight 40 oil for diesels without emissions.. dont know if that will help or not but maybe get a few more hours or seasons out of your equipment.

Best of luck to you
 
I know nothing about this ... but what about mixing in some oil in the fuel to aid with compression? Have heard about using light weight oil / transmission fluid in the intake to help build compression when trying to start old, stubborn, worn out diesels.
 
You have a compression tester? If not, You could pick one up for cheap and test it using the two oils. Report back if you do! Personally I don't think oil is going to help much, but I love being proved wrong.
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(Sorry for delay, thought I would get an email when I get a reply, need to adjust settings) I do not have a compression tester, I know it needs a rebuild but that isn't a high priority since it is only used for a 3 point backhoe at the moment. It only has issues starting. It runs beautifully and efficiently when running. When it is hot it starts as quick as our 99 NH 3930.

My goal isn't to magically fix all my engine problems, I just don't want to make them any worse.

I thought perhaps it would make it start easier if it had lower weight oil, but I didn't want to make it have lower compression. I guess my remaining questions:

Does anyone know what factory oil these had?(I have no paperwork on the machine)

Does oil weight have any bearing at all on compression?

Is there a way to tell the weight of the current oil at a glance? (I assume not)

Overall, what oil should I put in this machine. It hasn't had an oil change since I have been involved with it.

Here is a pic:
 
If you don't know when it last had an oil change do one now!.
A high detergent 10w40 or 15w40 should do the trick, I say use a high detergent oil because with lots of blowby you will be contaminating the oil pretty quickly.

The oil has no bearing on compression, the factors there are initial engine design and ring, piston and bore wear, and valve seating issues. I could include head gasket but if that has failed you would have other issues apart from poor cold starting.

A couple of tricks I've learned for starting old worn diesels are;
A little (and I mean maybe a couple of squirts from an on fashioned oil can) oil into the manifold will help seal the rings during start up. Be warned, you will know you have put too much in if the engine locks or the rings get smashed on startup.
A blowtorch on the inlet manifold will heat up the intake air which will help initial fire up, and a flame across the inlet (take the air cleaner off first!) also helps.

Claud.
 
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Originally Posted By: Austin_J
Overall, what oil should I put in this machine.


I'll say it one more time, Austin -- Mystik JT-8 15w-50, which is available at your local O'Reilly.
 
It has a block heater that kicks the gfci the second it is plugged in. A dipstick heater? Never heard of those, I'll look into it. That is cheap and simple. It is getting oil and all filters changed when spring comes along with the NH 3930. Just to let you know how bad the compression is, it has had nearly 1/4 can of starting fluid sprayed in it at one time and it didn't lock the engine up. I am starting to consider trying my first rebuild on this tractor this summer though. If it had a great running engine it wouldn't be hard to trade it for a full size backhoe if I throw in a couple unused bush hogs and a box blade.
 
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That Mystik looks pretty good. On some other forums folks have had real good results with it. It is also not terribly expensive.
 
Nothing can really save you if your engine has this problem. However, I used Redline oil in a Saturn ION that had compression below spec. It did raise the compression a little, but not enough to save the car.

Good luck.
 
No oil in the world will raise compression...
But going with a 0w-30 will raise the starter speed and
that helps a diesel start.

A blowtorch in the intake works great!
Jump start the [censored] with 24v will also make wonders but can
take a toll on electrical parts.
 
Thanks for that pic! That is great. I have never seen any documentation on Longs except on ebay for ungodly prices. The cool thing is that backhoe is actually Long Brand as well. We didn't even get them together, but they were practically designed for each other.
 
You are welcome, what you got there is a tractor that with some minimum maintenance will serve you for another 20 years
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Ours had 3800 hours...back in 2000 when the ODO broke...probably like 10-12K hours by now and 1/3 of the those spent at 2000+ RPM as we use the PTO to power an atomizer.

What you need to pay close attention is the electric starter as leaking diesel on the engine block will sip past the gaskets. Once inside the starter it will mix with the dust left behind by the brush and will put a heavy strain on the battery and making the starting a pain in the bum.

As for blowby...our is blowing smoke on the PCV but it starts in 3 sec flat even when cold outside.

If you need anything from the manual just let me know.
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