TheSamba.com :: View topic - Expensive-sounding noise, time for a Subaru? heh

Sat Apr 12, 2025 7:32 am

Sunk or lost seat. No damage. That’s because you spend your life worrying about, and helping others, and the Creator smiles on you.

Sat Apr 12, 2025 9:15 am

If I can pull on the valve end/spring without the stem coming out or wiggling around, can I relatively safely guess that the end wasn't bouncing around in the cylinder?

Sat Apr 12, 2025 9:29 am

If you have a valve head and a seat loose in the cylinder I would think you would be hearing a loud metallic noise and that the engine would have bent a rod and/or locked up.

It will be interesting to see what you find.

Sat Apr 12, 2025 10:05 am

Quote: If I can pull on the valve end/spring without the stem coming out or wiggling around, can I relatively safely guess that the end wasn't bouncing around in the cylinder?

Ah...sorry...had not noticed that you have the rockers off. So, one exhaust valve and spring assembly sitting up what looks about 1/8" to 1/4" higher right?

So, either you snapped a head off and the remaining stem is too rough to pull out through the guide...but if that happened, then about 100% of the time, the spark plug you removed would be trashed.
Even at idle rpm, the pistons make 15 cycles per second and the spark plug gets mashed by whatever parte are bouncing around in the cylinder.

So if the plug came out clean and undented....its likely something like the seat came loose (as others have noted) and flipped around edge-wise...maybe didn't fall out yet...and that allows the valve to receed farther making the stem higher. In that case....you are lucky.

New head.

Ray

Its also possible

Sat Apr 12, 2025 11:45 am

edit. wrong photo. Not the OP's.

Sat Apr 12, 2025 7:29 pm

I wouldn't have ever described the noise as quite metallic. More like an exaggerated/louder version of the noise when the Bus has sat for a while and the lifters aren't pumped up.

Spark plug had no obvious damage, and they are the tri-tip type, so it kinda seems like it that might be even more susceptible to damage if there were bits flying around in the cylinder.

Also, the pushrod was not obviously bent upon removal, though I didn't roll it on glass or anything, just pulled it out and set inside the bus for the moment.

Sat Apr 12, 2025 7:46 pm

A dropped valve guide can make a heck of a racket with very little debris, sometimes there is lots of smoke
Didn’t touch the plug either

Thu Apr 17, 2025 8:22 am

Current state, as of last night.

It's been difficult finding time to work on this, while also feeling the necessity to hurry (with people wanting to book us/the bus for shave ice selling!)

Got the engine out yesterday morning with a rare time off from clients. Did a bit of de-greasing with the hope that will make work a tad more pleasant.

Will get off a bit early tomorrow; hope to make more progress then and at least get the one head removed. I hope to be able to do that tonight, but that hope feels like a bit of a pipe dream, especially if a certain 4.5 year old doesn't want to go to bed easily.

I hoped to get more work done on it last night, but we had some friends over for shave ice. Silas' old daycare closed a couple months ago and he was missing his playmates, so they came over for a bit.

Thu Apr 17, 2025 8:27 am

Any recommended sources for heads? Recall that this engine is out of an aircooled Vanagon.

Thu Apr 17, 2025 8:40 am

These any good?

It seems like a familiar name... Though I thought I'd also seen that they still need some reworking before being used? I could easily be thinking of something else. Ad says they're ready to install.

https://aapistons.com/products/aa-2-0l-type-4-airc...7167162447

Thu Apr 17, 2025 10:19 am

Install a Subaru motor. They never blow up. I have got over the last year, two Foresters with grenaded motors where I put in used ones. Probably just a freak occurrence. Since you can get those for free and used motor costs around $500 then once done and cleaning it up you have a $5K vehicle, I feel bad because that gravy train has stopped since Subaru motors never go south.

Fri Apr 18, 2025 6:40 am

Sounds to me like a broken spring not a serious internal problem.

Sat Apr 19, 2025 11:59 am

Well, shit.

I can see a little gap in the valve seat(?) at about 11:00, I suppose that is probably the source of the bit of metal that is embedded in the head.

I'd be tempted to try to smooth out the dents in the piston, except for that one big divot near the edge seems like that would make it riskier than otherwise...

Amazingly, it doesn't really seem like the cylinder was catastrophically damaged. I don't see any scratches. The light spot was likely caused by the bit of metal; it is detectible with a fingernail, but not a catch.

...I'm crazy to consider smoothing things out and running the piston, right?

Is it crazy to try to find a used piston, a set of heads, and throw the engine back together?

At least then I could get it back on the road for local use with the shave ice stuff.

Sat Apr 19, 2025 12:28 pm

Well that's a first for me to see. Wow!

It's risky reusing the piston, IMO.
Remove the cylinder and see if the top ring groove has been crushed by the broken valve seat. That will tell ya if it needs replacement.

P&C's are cheap.

I get that you are making an effort to get the bus back on the road for your side gig. If it's only gonna be used around town, you might get away with you plan above. But, it's risky.

Sat Apr 19, 2025 1:03 pm

piston toast. Head toast. Not worth trying to repair those parts. If the Cylinder and piston are original then they are probably Kolbenschmidt, and you might be able to buy a single used one and re-ring it, being somewhat close in weight. I would probably hone all the cylinders and replace the rings, try to find an individual that matched. Or buy a new set of PCs. As to heads, if it were me, I would call Len and tell him, "Len I need a set of (square port / oval port whatever they are) heads for a 197X bus. I know you hate working on that stuff but what would it cost me for a set that I can trust?" Then give him what he wants if he will do it. What he hates is to spend time on the phone answering question after question that takes him away from all the other jobs he has going on. Whomever you get heads from, have the valves back cut.

Sat Apr 19, 2025 4:09 pm

I have seen pistons and heads that have seen far more damage than that back in the day that got a lot of additional miles put on them. If the rings are free, then its a monetary decision whether to reuse or replace. The potential for a crack in the piston's head that might propagate away from the one divot would certainly be of concern.

Sun Apr 20, 2025 4:34 am

Get that gunk off the piston, form to clean metal, before you make that call.

If you aren’t tripping the car and will roll it around town , you can run that piston…probably….after clean up, until next tear down next winter. Save that labour for that tear down

Sun Apr 20, 2025 5:41 am

When I dropped a piece of brass down the intake, I picked it out of the head and piston on my T1. Then i peened over the divots. Where one went near the piston edge I filed the piston edge gently.

I put it back together and have been driving it like usual since.

Sun Apr 20, 2025 8:25 am

I had an issue years ago in this GEX hydraulic lifter piece of shit that is still in my single cab and seems like it refuses to die (despite my best efforts, and no oil changes in 14 years.. yes, 14 years)

It has mismatched heads, a piston dressed with a dremel re-used rings on a 'fresh' hone job back then.

It's the most gutless pile of shit I have ever driven, but it runs pretty good in spite of it all.

doesn't help that I have been hauling anywhere between 1800-2200 pounds of shit to the scrapper

So depending on what your expectations are, don't listen to the forum at large. I don't go far out of town, and have an engine ready to go for this...which I thought would have been needed in a year...14 years ago...

Sun Apr 20, 2025 9:20 am

I posted yetserday and for some reason it did not post....anyway...kinda along the same lines as what skills said.

Before you buy or throw anything away, pull the cylinders off and inspect to see:

1. check the ring groove near that damage. If it measures fine then its fine....fine enough.

2. Measure the piston skirts. If they are still in range...fine.

Then I would:

1. Grab a dremel with a 360 grit rubber wheel and take the hard/sharp edges off of the dents in the piston. I have run worse than that for 50k miles with higher compression. I had valve dents in all four pistons from a cam disaster and they ran fine (all I could rfind at the moment).

2. Get new rings and run a ball hone through the cylinders just to get them a new tooth.

3. Lap the top sealing surface of the cylinders on a sheet of glass.

Why do all of this? Well....if they measure out right they can be fine for MANY miles...depending on what you want out of this engine, If you are willing to put it back to gether while you are collecting parts for a complete rebuild down the line....it can work fine. Ray