Saturday, July 11, 2009

I've been rebuilding the wrong motor...

The piston from the motor we bought after some cleaning. There's no manufacturers part numbers. The edges and surfaces are indistinct, like somebody used a genuine piston to make a casting and came up with this knock-off.

I've been taking apart the engine from the 1986 VW Westfalia because it failed on the way up from Barra de Navidad to San Carlos (about 1,000 miles- see previous posts). As I get further into this motor, I'm finding some specific things: the pistons and cylinders don't have a manufacturer mark, and that tells me that the last rebuild of this thing was done with cheap, generic parts... the oil pump cover/seal showed signs of being reused after getting scratched up and scored... a big no-no. The cylinders are deeply scored, suggesting to me that the work in the crankcase was done with less-than-perfect attention to alignment, bearing dimensions, etc. The rebuilder smeared sealant at the bottom of the cylinders (which didn't work, and peels off to clog the small oil ports in the engine, as well as clogging piston rings and oil pumps). Disgusting.

The spare engine, however, indicates tight tolerances in the crankcase, smooth bores, clean pistons (all with the all VW parts numbers) and proper sealing procedures. So, I'm shifting my attention to the motor the rebuilder was supposed to have picked up (and refunded us $600) for the core return. It appears to be a much better engine.

The piston from the original motor. No cleaning done. Notice manufacturers part numbers. The edges and surfaces are clean, clear and distinct.

Why was it replaced to begin with? The ground strap failed to conduct enough voltage between the engine block and frame, so when the high voltage spark plugs fired (at about 1000 times a minute, each) the spark arced to the aluminum heads. Most of you know that aluminum is smelted with electricity... and that's what happened to the heads.

Below: The aluminum heads from the original engine showing melting of areas around the plugs and valves. These will go to recycling.


Chrissy y Keith said...

dang, that sucks. You impress me with your knowledge and patience. But, the work for the Westy is a labor of love. right?

MxSailor said...

It's more work, and I probably wouldn't do it if this was my only car. But, I feel fortunate I have a better engine to work with. I think it will last longer, run better, have fewer problems over the long term.

"Usually problems are opportunities in disguise... "

Liz said...

Wow, great updates.
I had quit checking this for awhile, the posts were few and far between.
Good luck with your (too) many projects.
Mata ne

MxSailor said...

Thanks Liz. A friend of that crazy Brit on the concrete boat, aren't you? I suppose you saw my little vid of the launching of AJ?

Liz said...

Yep, the vid was great.
Hope we get to see another one in the near future.
AJ simply cannot lie fallow any longer for the sake of a "stealth BF" Her first loyalty should be to her beautiful boat, to realize a dream adventure. We must work on her harder ;))
(So I can come visit !!)
Mata ne

Rambunctious Rambles said...

So many VW's, so much trouble. My last was a 1974 Bus which the factory said would do speed and not cave. O.K., I caved it on a guardrail a year later, but it was beginning to sound loose after a year of interstate travel in those times. Speed limits?? It did have a lot of power and did very well on long trips. Because of the timing, I actually got back in insurance more than I paid due to the difference in the mark at that time.

My best VW demise was a 1971 Squareback with a newly rebuilt engine which I took on a cross country trip in some year after that. The builders, who were more into performance than durability, did not use the typical gaskets, but used sea;ants which they felt were better anyway. So it handled the first leg, from the west coast to Misszouri, but on the return leg, loaded with an additional some pounds of cased books, not so good. Coming up out the Colorado river on a hot summer day the car pulled well, but once over the top and coasting, it totally melted down Those darn VW's, they need the intake air to cool, and once that is shut off, they are in melt down mode if they are over-heated. It took the CHP and a tow truck to get me to Indio for a total rebuild. Sucked. That one, from a VW dealer lasted until I traded off the car. My last was a 1972, which was o.k., but still required the tinkering to keep it on the road. No more air-cooled's since then, and happy for it.

MxSailor said...

Liz- I think she's looking for an dirt-based house to live in now, maybe house-sitting if she can get it. It's so hot in a house now compared to the water. It would be fun to meet you. Somehow my invite to her new blog got lost, but I remember your posts from the "mata ne" greeting.

RR- Lots of people say the waterboxer engines were VWs biggest mistake. But I suspect that I, like you, overloaded the van... and then I hit these steep, windy two lane roads in the Sierra Madres ("we don't need no stinking oil!") and that blew the gaskets. I look at it as an exercise in patience, creativity and swearing %#@&!