I'm going tomorrow to look at 2 MH's one a gasser one a pusher, the pusher is a 1997 with a 275 cat.. 100k miles.. how do I check for electrolysis in the cat or is this a non issue? thanks!
Cavitation is only an issue with sleeved cylinder engines. Engines like the Cummins B series don't have sleeves so will never have this problem. IF you have a sleeved eng then you need to keep up on coolant chemistry.
Yes, I suspect cavitation or cylinder wall pitting (cavitation causes cylinder wall pitting) is the issue you are referring to.
The only diesel engine I am aware of (no experience with Navistar/Ford engines, as very rare in Class A motorhomes)that do not require SCA or the new-generation OAT-based coolants is the Cummins B engine.
But, not sure that the chassis makers don't use the same "low silicate for diesel with added SCA" coolant in the cooling systems for chassis with the B engine as well-- you would need to check with your chassis maker.
I have a international roll back with a big diesel in it.. one of the guys that use to help me got a diesel shop to run a (what he called electrolysis) test on it.. it was fine.. a few years ago I test drove a toter home with a new detroit in it.. the owner had just replaced the motor because it was "eat up" where he didnt do any "electrolysis".. I think that was about a 5k fix.. and I may be using the word electrolysis wrong here.. that's just what they called it..
The additive is added to the radiator...was a standard maintenance procedure in large diesels...Baldwins FleetStrip kits are the most widely used/available. Can be a very costly repair. Now the smaller modern diesels may not require it.
Cavitation can be an issue. Never heard of electrolysis on any diesel engine being an issue.
Cavitation is caused by not maintaining the coolant/ not changing it as prescribed. Coolant maintenance with "regular diesel coolant" involves replenishing the SCA(Supplemental Coolant Additive).
BTW, the Caterpillar engine you are looking at is NOT a linered engine, so cavitation would not be an issue.
Cavitation is probable what you are concerned about. There is no way to check the condition of the sleeves. There are no warning signs. Where diesel cylinder cavitation is concerned, the bubbles are formed by the rapid flexing of the cylinder wall liners as the high compression, high energy diesel combustion process takes place. Much like if you filled a plastic liter pop bottle up with water and rapidly flexed the sides of the bottle back and forth with your hand. Bubbles form without any heat present. The bubbles in diesel cylinder wall cavitation don't explode, they implode due to pressure. It is this implosion against the metal surface that causes the pitting to form in the outside of the cylinder wall. Eventually the prolonged pitting will become a hole. Water/coolant enters the cylinder, and thus we have engine failure (usually via hydrolock). Unlike gasoline engines, all diesel engines experience some level of inherent cavitation, some worse than others. Only thing you can do is check the ph of the coolant and maintenance records for coolant flush and change. If the engine has extended life coolant or has the ph checked and has been serviced regularly then the chances of cavitation problems will be minimal. No maintenance = big problems.
They make test strips for the additive. A truck garage may give you one stip and show you what the colors mean after a test. If you are buying from the owner, ask very general questions to see if the owner knows, thus telling you if the know what they are talking about. Pat
Interesting question. I'm not familiar with Electrolysis in engines. Do a Google search, lots of info available. It sounds like the OP is doing his homework before buying a unit.