Perkins 4.108 - oil in coolant

[sf_pearl]

Just a little update on my progress here.


New head gasket installed, and run up to ~190F-ish without coolant. What a job, but got the head and crankcase top pretty shiny.


Next up is reconnecting the fresh-water coolant system and running some pure water and dish detergent through it a few million times.

[Compass790]

Dont worry about detergent on your mechanical seal ( ceramic )
Mechanical seal seller told me to put it on the seal before initial start of a water pump for tank water.
I would have recommended Loctite 518 master gasket or flange sealant for head gasket but too late. I have re-installed a damaged head gasket on a 23:1 compression ratio diesel in an emergency & it worked for years.
good luck

[sf_pearl]

Quick update: Project (I think) complete!


After many, many gallons (well, okay, a dozen or so) of flushing with straight water and dish soap, I have the beast back together with the new head gasket, antifreeze and the thermostat working. There is perhaps the tiniest trace of slickness on the coolant that I am certain (I keep saying to myself) is residual from the flushing. Had it out a couple of times getting the temp as hot it would get in the chilly SF bay (got it to 150 at least) and so far it's run for ~3hrs without any sign of more oil in the coolant.


I will remember to re-tension these head bolts at the end of the 2021 season, which I sure hope is around 25 hours.


Thanks to everyone for advice. The Mighty Perkins lives for another day of sailing!

[Compass790]

Good news.

thanks for reporting outcome, always interesting to hear what it is.
Question for you, did you use a head gasket cement/sealer on it & if so what type?
Just want to know what else works than my usual brew which is expensive.

Strange to me that leak path wasnt obvious but if it was only between water & oil galleries I guess it might not be.

[sf_pearl]

Originally Posted by Compass790

Question for you, did you use a head gasket cement/sealer on it & if so what type?

I didn't; I used a gasket that had the red sealing rings around all the holes. It came from Parts4engines.com in England, and only took four days to get to the w. coast. I don't remember the price, but I bought a gasket kit that included many top-end gaskets.

Originally Posted by Compass790

Strange to me that leak path wasnt obvious but if it was only between water & oil galleries I guess it might not be.

Yeah, I'm surprised it wasn't more obvious on either the gasket or head either. With close inspection of the gasket it seemed like there was a little compression leaking on one side of all four cyls as well, but I can't say I've had enough experience in inspecting head gaskets to be sure. The one thing that was certain is that (some of) the head bolts weren't half tight, due to my omission of retensioning after 25 hours.

[Scubaseas]

Glad to hear it's resolved.

If your new gasket has red lines around the ports you should follow manufacturers instructions for installation. Which most will say is clean, clean, clean and then either put it on dry or use Spray High Tack (which also does a good job of holding it in place during assembly). In the old days of asbestos gaskets enclosed in copper sheets one could use good old Permatex 2 aviation goop or Indian Head Shellac, or Gasgasinch but new composite, single use gaskets are designed to be used dry. In the late 70's to early 80's you saw a new generation of gaskets come out as asbestos was restricted. Newer style gaskets will glue themselves to clean surfaces, sometimes with an activator/primer coat applied but using an adhesive/sealant may actually be counter productive.

Loctite 518 is a great anaerobic gasket material but I would not use it on a new head gasket if said gasket had adhesive compound (the red lines) on it. 518 is wonderful for flanges and things like extension housings and timing covers but not so much for head gaskets. It's also really good at clogging up passages if you put too much on which most people do. It's kind thick for a .004"/.1mm max space/warp and is only good to 300*F. High Tack is good to 500*F and as a spray goes on even and thin.

Just my opinion. YMMV. If I was forced to reuse a head gasket then sure, why not use 518.

It's good practice before taking a head off to check the bolts to make sure they can be torqued properly. One at a time and in reverse order of sequence note position of bolt, loosen and then tighten to spec and see if the bolt is in the same spot. It should be. If not either your bolt is stretching or the hole is. A lot of applications these days use torque to yield bolts that require replacement of the bolts when changing the head gasket. The Perkins isn't one of those engines.

It's very hard to see oil trails or where it may have been traveling from oil gallery to cooling passages. If you had used a tracer dye in the oil and run the engine, maybe but probably not. Sometimes you can see where it's a lot cleaner and get an idea that way as oil is a detergent but seeing where an oil leak was in a head gasket maybe tough unless the oil gallery area of the gasket has in inset rubber or copper seal that's clearly blown out.

[sf_pearl]

Can't believe I'm still updating this thread, but I'm feeling like this problem may never end.

I seemed to have lost about 1/3q oil over the last season; more than the engine should be burning at ~200hrs. I sopped it up in the overflow tank after each trip with strips of oil-sorb. Seems like it still must be leaking.

I just re-tensioned the head bolts (and adjusted the valves, and all the attendant pains of flushing the system again), changed the oil and said f-it, I gotta sail this season. I also jumped the oil cooler for the season, just because.

Driving me pretty properly nuts at this point. I sure didn't see any damage to the head when I had it off, and it had never gotten hot.

[Lepke]

If it's still leaking, I doubt it ever was the head gasket. That leaves the heat exchanger or a crack. I'd get the heat exchanger retested.
Oil pressure is higher than coolant pressure, so if there's a hole in the exchanger oil goes into the coolant. I've chased leaks in heat exchangers that only leaked after everything heated up and the pin hole expanded - usually a soldier point. Something that might help is a higher pressure radiator cap. But it's a bandaid for something that could fail at an inconvenient time. Or you could have a shop rebuild the exchanger.

[sf_pearl]

Thanks @Lepke -- guess we'll see this season. I jumped the heat exchanger with a copper pipe.


I tried that before I decided it was the head gasket, but it's possible that enough oil got in the coolant that the residual just kept re-appearing every time I took it out. I did a pretty decent flush (with the dishsoap treatment) this time, so we'll see.

[skipperpete]

I’m guessing that you have the dual oil cooler, one side for engine oil and the other side for the Borg Warner and have eliminated the cooler as a candidate with the bypass pipe and since the engine is losing oil and not the transmission, we could assume that it’s definitely a lube oil leak. If I was the bloke you hired to solve this problem, the first thing I’d do would be to check the oil pressure and the rate of oil flow through the rocker gear,.... the drilling from the camshaft bearing through the block that then meets the gallery in the head is a reduced pressure flow gallery and not system pressure so, if the engine rebuild bumped up the system pressure to the max... 60psi , or there’s no pressure drop between the camshaft and rocker shaft it’s possible that the seal between the head and the block has started leaking again.... across to the waterway that shares the oil gallery seal . It could be as simple as a blocked rocker shaft connection that’s causing the oil to cross into the coolant circuit... or not[emoji848]