Cummins Canoe (A Stepvan Story)

[AmargosaWayne]

Priorities.

 

[PlethoraOfGuns]

Got to have them priorities. Otherwise, what is life worth?

 

[Calypso]

You know how many times women have told me that in the past?


Huh?

The dang thing won’t let me laugh at you… so here it is.

 

[KarlH]

It's very quick with two people, I love it. I'll time us this time. Hardest part now will be removing the passenger seat with all that extra hose and wire and stuff that goes out to it. And with the compression ratio it's supposed to have, the amount of boost should be ok. But I'm not sure. Need a professional on this on.

I didn't mean that boost caused it, just that dropping the compression may get you the performance/reliability balance you want.

What I always heard from the R&D engineers I worked with is that ideal compression is ~15:1, and higher compression in diesels is strictly for cold-starting. I can't find a good source for that right now, but this thread popped up in a search:

https://www.speed-talk.com/forum/viewtopic.php?t=36147

The higher pressures also causes more blow-by and also bore friction losses.

... Do engines make more power with more compression? Up to a balance point where several lines cross - I've read studies of it being in the 15-16:1 range, but it depends on so many things, that you can't put an exact number on it. High compression also requires more starter, more head gasket clamping, more piston dome, more caution with cam choice and installation, and more caution when tuning.

So if that's accurate, it may be possible to lower your peak cylinder pressure a lot while keeping your power and mileage. The downside would be needing to use your block/air heaters at higher temps.

 

[KarlH]

The downside would be needing to use your block/air heaters at higher temps.

Bad wording, I meant at higher temps than you normally would.

 

[PlethoraOfGuns]

The gods have spoken!

This sweet deal popped up and I couldn't let it slide. Cummins 4bt out of a Ford step van. A little cleaning, flip the oil pan around, new seals, fluids, and we're going to drop her in! That other engine we have is a lemon, I've come to terms with it. I'm giving up on it. This one runs so what do we have to lose?

 

[mudbunny]

Fingers crossed!!

 

[mudbunny]

Progress report??

 

[PlethoraOfGuns]

No progress on van. Hot tub and shower still work great. Had some work in the mountains of Montana to do, so delays on repair.

 

[PlethoraOfGuns]

We got some updates for ya'll! Finally secured time to get this engine in the garage to be prepped for the swap. Been getting around in an old manual Honda Fit while the van has been down. Boy, those are great little cars! Really nice getting 42mpg. Maybe we can flat tow it behind the van?

Anyway, time to get working on this thing. Got it for a good deal. But it's old, who knows how old, but it runs. So we're going to do a quick reseal.

But upon further inspection, I was finding things that I did not like. Many hardware bolts with nut spacers? I have no faith in mechanics. Will be replacing hardware and any old bearing and seal/gasket.

Also there are these messes. Like what shortcut was someone trying to do to cover this leak up? To be fair, in order to replace the gasket behind the timing case, you need pull the camshaft and injection pump. Well, now the engine is pretty much almost fully disassembled. The entire fuel system, exhaust, intake, alternator, hydraulic pump, fan pulley assembly, oil pan, rocker arm assemblies, lifters, camshaft, and a bunch of other stuff is laying everywhere. I did not remove the cylinder head from the block. We're going to assume the head gasket is fine. Also, these oil pumps last forever, and the water pump is literally the easiest thing to change so that is staying in.

 

[mudbunny]

Now Is the time to fix all the quick fixes so they don't reappear. Good luck with the "new" engine.

 

[PlethoraOfGuns]

Thanks. We're hoping for the best. This was supposed to be an easy swap, but I may have been scammed on this one. Not sure, but the more I dig, the more signs of neglect are found. I think I might throw the old broken engine and rebuild it on a rainy day as a spare.

 

[Happy Camper]

If you have the knowledge and ability to do so, you should. Better than scrambling if something happens.

 

[PlethoraOfGuns]

Yep, pretty deadset on having a spare engine in storage somewhere. Seems silly, but I have the worst luck! Got both engines in garage now swapping parts and such. Will update this weekend.

 

[SpinnerUp]

Personally, if I had it torn down that far, I would pull the head to check for flatness and valve condition and replace every gasket, o-ring and seal. Especially if I had as much bad luck as you say you do Asking for problems otherwise.

 

[KarlH]

Personally, if I had it torn down that far, I would pull the head to check for flatness and valve condition and replace every gasket, o-ring and seal. Especially if I had as much bad luck as you say you do Asking for problems otherwise.

Also a good time to do the "killer dowel pin" fix, but I assume he's done that already.

The other problem area I found on my van is the engine mounts, especially on the right side. I'd completely redo them if I were pulling the engine.

 

[PlethoraOfGuns]

Problems happen if I touch things and if I don't touch things. I wasn't planning on taking anything apart, need this engine running yesterday! I'm assuming the camshaft will end up breaking on this engine. Only thing that hasn't been a problem yet. But I am a pro at killer dowel pins now though.

 

[PlethoraOfGuns]

Well, that was fun. We ended up changing everything but the piston rings and bearings, haha. I know, we should have just done the whole thing, that's what is gonna happen to the old broken engine! Ready to throw this thing back in.

Finally got some help to pull this engine out.

Worst part was having to remove the passenger seat with all the hot tub controls in order to get the engine out.

Did I mention how easy it is to do engine swaps in this thing? I do it once per year, so you know I'm getting good at it.

Multiple Cummins engines, oh boy! Swapping parts over from one to the other. Needed to steal the oil pick up tube, intake, and coolant hose fittings off the old engine.

Took three days, lots of cussing, and of course dirty hands, but the "new" engine has many new parts and all new seals and ready to get thrown in!

 

[mudbunny]

So, up and running? Hoping all is ok.

 

[PlethoraOfGuns]

Things were going well, full of challenges and tribunals. And then it all went horribly wrong again...

Took a bunch of hands to get the hydraulic pump pack on as we never disconnect the lines, but instead remove the pump while it's in the vehicle.

More tragedy stuck. Moving things around, dropped the turbocharger on the ground right before I installed it. the leverage from the oil pipe return seemed to trash center bearing housing. That was an expensive hit. It was pretty much a new unit, not sure what to do about that. Rigged up an old turbocharger I had laying around instead and got it running! Started right up once fuel lines were bled. Drove it around, everything seemed well. Then boom! Smoke was everywhere and the dipstick shot out of the engine. It's been a terrible last few weeks. I have no idea what to do with this piece of junk. I guess I need to try engine #5? Still living in the van, but it's still stranded.