Ford Lehman, oil brand and exhaust smoke

[N97746]

Has anyone noticed their Lehman, or any diesel for that matter, tending to smoke more or less with a particular brand or weight of engine oil?
Seems like I am getting a lot more smoke recently having switched to Rotella.
Thanks.

 

[rslifkin]

Does yours consume a noticeable amount of oil? Unless there's significant oil consumption I can't see different oil causing a change in exhaust smoke.

 

[Figment]

Lighter weight oil will absolutely get past the rings and valve stem seals more than heavier oil.

 

[KnotYet]

Which Rotella? An old NA diesel will be happy with Rotella T4 15w-40.
The T5 and T6, while they are good for newer turbocharged diesels, might
slightly increase smoking and oil consumption in an older, worn engine, IMO.

 

[Pete Meisinger]

Hmmm, smoking from the exhaust could be a large number of issues. Unless you were using a very heavy oil previously I doubt that going to good diesel oil would cause an increase in smoke.

I'm think it to be more of a coincidence. Could be the injectors, could be steam, could even be bad fuel. I'd keep looking. Or go back to your previous oil and see what happens.

pete

 

[BruceK]

Cause and effect is more likely than coincidence.Easy way to determine if the change of oil type is the cause is to switch back. If the smoke increase reverses, it was the change of oil.

 

[N97746]

Sort of embarrassed to admit it but I can't remember the weight and type of Rotella I used. This was done in early spring and after a lot of work on the engine, I am just now getting to test run the engine. I'm pretty sure I used the conventional formulation. Blame it on impending geezerhood.

One variable that might play in, the boat is on the hard and with the lack of cooling water for the exhaust I haven't been able to run it up to operating temperature. I'm using a completely new fuel system with fresh fuel.
Running at a fast idle, holding oil pressure at 55-60 psi.

What got me asking the question was my brother telling me that when he used Rotella in his Yanmar it would smoke. I've used Rotella in gas fueled trucks with no untoward effects. Just was wondering what the TF members experienced.

 

[Tired Trawler]

Greeetings! I have used Rotella T4 15/40 for several years in our ancient Ford Lehman 120hp. Noticed visibly reduced smoke. In my former life as a Volvo Penta specialist, our commercial operators swore the Rotella T4 reduced smoke in both wet exhaust & dry exhaust applications. I also noticed much faster initial oil pressure build up over the old straight 30 weight lube oils. The other oil the commercial boys were using was Chevron Delo 400 15/40, but they felt the Rotella T4 gave a cleaner exhaust. Your observation regarding the boat being out of the water is spot on as you are not coming up to operating temp, I assume that you are supplying water to your sea water pump or are you keel cooled?

 

[Delta Riverat]

My last change (I did it myself) was Rotella T4, 15/40, 8 gallons. Smoked way less on start than the old black oil did. A hundred hours later and it's still brown -

Get a lot of diesel fumes on cold start, but not a lot of smoke.

 

[grandbanksbayfield]

My Lehman 135 in a GB32 always gives off some white smoke until it has warmed up about ten minutes at 700 rpm. It did it with Rotella 15 - 40, Rotella 15 -40 T6 and now with non-synthetic Valvoline diesel 15-40 I bought recently from the Cummins dealer. Nothing changed. I went back to non-synthetic because the old engines do not need anything more. And it is half the price!

 

[catalinajack]

Which Rotella? An old NA diesel will be happy with Rotella T4 15w-40.
The T5 and T6, while they are good for newer turbocharged diesels, might
slightly increase smoking and oil consumption in an older, worn engine, IMO.

Why would that be? T4, T5, and T6 are all 15W-40 multi-vis oils.

 

[rslifkin]

Why would that be? T4, T5, and T6 are all 15W-40 multi-vis oils.

I see no reason it would make a difference. And even if the semi-syn or synthetic versions burned slightly more for some reason, that doesn't necessarily mean more smoke. Generally I've seen that synthetic oils make less smoke when burned in an engine. Plus, it takes quite a bit of oil consumption to produce visible smoke anyway.

 

[alormaria]

Yes. I had significant smoke and burned 1 qt of oil when I had to use Pennsoil 30wt. Next year went back to Shell Rotella 30wt and everything went back to normal. No smoke, no oil burning.



Scared the hell out me.

 

[new2trawl]

I'm running twin FL 120s and have run Delo 400 30w for the last 7 years in my 83 OA MK1. Other than a little smoke within the first 2-3 mins of a cold start-up, I've had no smoke issues using this oil. Now while the old FL 2715 manual recommends 30w, I may try a run of Delo 15w-45 at next oil change to see if the smoke at start-up dissipates a bit. Lehman's smoke a little, that's just how they operate. I love 'em. No electronics, easy DIVY. Just watch for any color change in the smoke.