Lehman 135 Antifreeze?

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David Rive

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I want to flush and change the antifreeze in my twin SP-135s. The manual recommends Zerex which I have, but nowhere in the manual or specs can I find what volume of antifreeze these engines use. Can anyone tell me?

Any other flushing tips are also appreciated, as I am doing this for the first time. Cheers.

David
 
I want to flush and change the antifreeze in my twin SP-135s. The manual recommends Zerex which I have, but nowhere in the manual or specs can I find what volume of antifreeze these engines use. Can anyone tell me?

Any other flushing tips are also appreciated, as I am doing this for the first time. Cheers.

David

Flush it with NAPAs flush or Cascade dish washer detergent.

Run it for several hours underway if you can.

Then flush with clean water. You can use a shop vac to pull out as much old fluid as possible.

Don't over do it with the antifreeze. More is not better.

I would recommend pulling out the thermostat before you flush and putting in a new one after. If you do pull off the expansion tank to replace the thermostat, look/feel up into the bottom of the tank. You might be surprised at the amount of sediment that can collect and harden in there over time.
 
Capt.Bill11,
Any engine manufacturer recomend flushing w dish washer detergent? Seems one should wash dishes w that.
 
If you drain them, they will take every bit of 5 gallons to refill.

Ken
 
Capt.Bill11,
Any engine manufacturer recomend flushing w dish washer detergent? Seems one should wash dishes w that.

I don't know what they recommend. All I know is what works and what a lot of diesel techs use to flush CATs, MTUs, MANs, etc. with at times.

When trying to flush out dirt, scum, rust particles, pertroleum product residue, etc., I would think detergent would come in handy. :D
 
Not sure if it applies to the 135, but the 120 can accumulate sediment at the back of no.6 cylinder,and there is what Brian Smith of American Diesel calls a "rear freeze plug" on the block which can be removed for inspection and to help flushing out.
 
Don't run your engine without proper coolant! Water is not a good enough substance for a diesel. For goodness sakes if you won't listen to me just Google "crevice corrosion..."

Yes, coolant has corrosion inhibitors because we are all scared of corrosion, there are other inclusions as well; if it was only necessary to keep things cool we could just put the anti-corrosion packages in the water and not bother with coolant. Using straight water or insisting on running expired coolant risks overheating and cylinder damage.

All those test strips and rigmarole that Cat and Cummins and others use to test their additive packages and insisting on scheduled coolant filter changing with their built-in additive packages is not just for the corrosion inhibitors.

Sorry, but "...run it for several hours underway if you can?" Sorry Bill, but I believe that is not good advice.

That brings up another thought - if you have left your engine with nasty antifreeze in it for so long that you need to flush, you are neglecting your engine. Changing the coolant is as important as oil changes and none of us here would leave the oil in an engine for ten years?

I think that attitude comes from gasoline autos which we all grew up with, most of us would only change the coolant at gunpoint, as long as the rad was full of something we were content. It's very different with cars than large diesels although Mercedes is quite insistent on antifreeze changes. I always assumed that Mercedes were just being consistent in their quest to squeeze every last buck out of their owners...but in fact their engines absolutely require good corrosion inhibitor packages.
 
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Just pour 1 container of antifreeze and then one container of water then mix the empty two containers 50/50.

If you only have 5 gallons, use antifreeze to flush the engine, not water. No risk of damage.
 
I would just add that you make sure to not under fill when you replace the fluid. Measure the amount coming out if you can to be sure you replace the full volume and if you find you replace much less than came out you will have to compress "burp" the hoses to get trapped air out.
 
"but "...run it for several hours underway if you can?" Sorry Bill, but I believe that is not good advice."

You really believe running an engine for a couple/few hours with water and coolant flush in it is going to cause any real problems?

What do you think will happen in that short time?

I know some of the flushes you buy say run the engine up to operating temp for 15 minutes or so and then flush out. But you can't get a lot of diesel engines up to temp at the dock so you might as well go for a ride for a while and get a good flush out of it.
 
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Hi Bill,

Yes, I do believe you can damage your engine, certainly with cavitation around the cylinders you run the risk of overheating. You will certainly add some damage to the cylinders that won't show up immediately, but it will shorten your engine's life. Why risk it?
 
Sorry, "cavitation erosion" not crevice corrosion. My bad.

"What causes pitting in cylinder liners?
A: Pitting in cylinder liners is a direct result of cavitation erosion. This type of erosion develops from normal mechanical and chemical processes that take place during engine operation.
Cavitation of the cylinder wall begins when air bubbles remove the wall’s oxide film, which protects the metal from coming into contact with oxygen and corroding. Flexing of the cylinder wall (after fuel combustion) causes the cylinder liner to vibrate, and creates vapor bubbles in the coolant. These vapor bubbles form on the outside of the cylinder wall and explode inward, or implode, resulting in tiny pits on the cylinder wall’s protective oxide layer. When vapor bubbles continue to implode, enough energy is released to physically attack the cylinder wall and remove the oxide film. Corrosion and pitting then take place at a high rate.
If a pit breaks through the cylinder wall, coolant can leak into the cylinder and contaminate the lube oil. A sludge forms that can interfere in ring and bearing functions. Wear rates increase significantly and engine seizure may result.

The best way to prevent cavitation from occurring is to follow your engine manufacturer’s recommendations on additive replacement. When using a standard heavy duty coolant, SCA (Supplemental Coolant Additive) should be added every 250 hours to help replenish the eroding oxide film. Caterpillar has recently introduced an Extended Life Coolant (ELC), which provides a substantial amount of protection and lasts longer than standard heavy duty coolants. ELC eliminates the need for multiple additive replacements – requiring only one addition of extender at 3,000 hours.
If you modify your cooling system, remember to keep the pressure cap furnished with the expansion tank. Removing this cap allows a lower operating pressure inside the engine. That will cause more vapor bubbles to form, resulting in cavitation."
By David O. Ahrens Commercial Marine Manager
Caterpillar Engine Products Division
 
I just don't see it. That kind of erosion is a long term issue. I find it very hard to believe you could do any real damage running the engine at cruise RPMs for a couple of hours.
 
A: Pitting in cylinder liners is a direct result of cavitation erosion. This type of erosion develops from normal mechanical and chemical processes that take place during engine operation.

Yes , but not in ancient engines where the cylinders are installed in a cast iron block.

The modern high power engines DO require SCA to keep the pitting of their bare naked cylinders at a minimum.

The method of controlling the collapse of cavitation is to move the bubble away from the bare cylinder wall with chemical slime.

Thats where the strips come in deciding if there is enough SCA.

The Modern engine needs a good 2 part flush to remove the old SCA ,
an antique like most trawlers have , just needs a can of radiator flush and rinse, rinse, rinse.

A 33% AF to water ratio has better heat transfer than 50/50 , so folks who will never see the cold can use1 AF to 2 distilled water, for enough protection.
 
All the major engine makers advise 50% but approve down to 33%. Is coolant so expensive? I suppose that it is if you are keel-cooled.

In the end, a large percentage of people's beliefs in engine maintenance is stuff you've grown up with, anecdotal evidence and corner-garage voodoo. My assertions will annoy lots of you because "a large engine shop in Seattle told me to do it this way" contradicts what I'm saying. Taking the time to post this stuff provides some information to add to your pile but basically, do anything you want to your engine, just don't throw the flush water in the ocean.

Happy Thanksgiving!
 
All the major engine makers advise 50% but approve down to 33%. Is coolant so expensive? I suppose that it is if you are keel-cooled.

In the end, a large percentage of people's beliefs in engine maintenance is stuff you've grown up with, anecdotal evidence and corner-garage voodoo. My assertions will annoy lots of you because "a large engine shop in Seattle told me to do it this way" contradicts what I'm saying. Taking the time to post this stuff provides some information to add to your pile but basically, do anything you want to your engine, just don't throw the flush water in the ocean.

Happy Thanksgiving!

I don't think anybody was advocating running long term with no coolant.

And happy thanksgiving to you too! :D
 
Here's my garage VoDo for the day ..
I always mix six parts distilled water w four parts no-diluted AF. Learned of that option from my BMW motorcycle manual. Long life AF as recomended in my manual. I think they would all recomend the 60-40 ratio but they probably are trying to keep it simple.
Then I mix up more than I need not being too fussy about how much more. I keep the extra on hand and label it "Mix". I drain after waiting a few minutes after a 20 min run for warm up. Then I drain through a ball valve that i installed for the purpose on the lowest point in the engine cooling system. I removed the original square head plug in this port on the after end of the block on the service side .. stbd.
Then I fill ... very slowly. And I think the "slowly" part is fairly important. Especially w hot water tank to engine plumbing and bus heater plumbing. I fill mine starting at the exhaust manifold and then finish by removing a pipe cap near the bus heater inside my setee. It's the highest point in the system.
Not done yet. I keep filling it untill it is 100% full at the bus heater and 3/4" down from the filler cap hole in the exhaust manifold. I assume all the air is bled out of the system through the vent w the cap bye the bus heater.

Flushing?
I've only flushed once and did it w radiator flush mixed at about a 25% level. Then flushed again w distilled water. I've never put anything but distilled water and the small amount of flush mentioned pluss the LLAF. I use extended life AF but probably don't need it as I made a point of having no aluminum engine parts exposed to coolant anywhere in the system. My manifold is a weldment of steel. Made by Klassen. They have been using these steel manifolds since the 60's.

Also I use a Murphy Switch that sounds an alarm when the coolant is down some. Probably saved our bacon once. Just one of the things I did on the repower.

I don't know if I'm subject to the cavitation issue or not. Intend to ask my engine supplier next time I'm in Seattle.
 
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Cummins Engine Company sells two types of cooling system flush. Both mix with water and are left in the engine while running for a time then rinsed and neutralized. Nothing new there.
Cavitation erosion takes a long time to eat through a liner but it does indeed happen. In the amount of time you are going to run an engine while flushing and rinsing nothing significant is going to happen. Also cavitation erosion does happen in parent bore blocks as well. International 6.9 early 7.3 engines where well known for needing to be sleeved at time of rebuild. I don't recall ever doing a Detroit but I think it was probably because if the block didn't pressure test it was just chucked as there where so many core engines around it was not worth the time or money.
 
Is coolant so expensive?

Nope , the heat transfer is better with least AF .

AF has only 5/8 the heat carrying ability of just water.

Most ancient trawler engines have very low pressure caps , so a higher temp of a pressurized car or truck setup does not work.

With the right cap, a coolant recovery system will work, but fill tanks are above the engine so this does not make cooling more efficient .
 
Does anyone know how to drain the coolant on a ford lehman 120? Can I use a vacuum and where do I suck it out from?
 
Does anyone know how to drain the coolant on a ford lehman 120? Can I use a vacuum and where do I suck it out from?

Clean the drip pan out then break loose the lowest coolant hose connection and let it drain into the pan. Shop vac out the pan afterward.

Then if you feel the need to get as much fluid out as possible you can as mentioned blow or suck more out with the shop vac.
 
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