lost compression

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I have a 71bus lost Compression can I just rebuild the top end

[67rustavenger]

Lost compression? Go find it!

You could do a topend refresh but, you'll likely find other issues, depending on the mileage since it was last rebuilt.

Remove the engine, tear the topend down and inspect the pistons and heads carefully.
While the cylinders and pistons are off the engine, look through the case/cylinder registers and have a look at the camshaft and lifter surfaces for damage.

Check your crankshaft end play. If it's more than .007-.008" it is likely time to go through the whole engine and replace the bearings/camshaft/lifters and seals.

You won't know what you have going on until you tear it down and inspect the parts.
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[airschooled]

Welcome to TheSamba, where we need details, and occasionally punctuation marks. Help us help you!

Perhaps you could just adjust the valves… but it’s kinda hard to help answer your question without having far more information. Did it happen suddenly? All cylinders or just one? What’s your mechanical skill set like?

Robbie
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[SGKent]

Welcome to thesamba.

You need to come back and tell us more for anyone here to really help you.
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[[email protected]]

talked to someone that use to work on them he said that the engine was probably over heated and burnt a valve the engine has about 10 to 12 thousand miles on it

[Xevin]

[airschooled]

Or someone f’d up a valve adjustment. Or didn’t adjust the valves. Or didn’t measure correctly. Or your engine is actually fine and it’s just slow like they all are.

Trust me, rebuilding an engine costs a little more than making sure your basics are covered. Like, four thousand times more.

Robbie
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[dodger tom]

you haven’t given any specific information about your situation despite being asked several times.

start with year of bus and engine type.

go back, and read each post, and answer each question.

if you don’t know how to answer, ask for knowledgeable vw mechanics or samba folk in your area.

then ask for a list of questions your could ask them.

the guy saying it might be a burnt valve might not be the best to help you troubleshoot your problem.
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1978 Champaign Edition 2 Westfalia
Would never find the time to keep up another classic air-cooled.

[[email protected]]

I have 1971 bus with a 1600 dual port was driving down the high way at 60 mph when all if the sudden it started losing power was able to get i home and that is where it is now. if anyone knows of someone that works on them in my area I would appreciate the help

[SGKent]

[lil-jinx]

it could be as simple as a clogged fuel filter,dirty fuel,burnt points,
over heat in Mi at this time of year,is that even possible
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1974 Bay Westfalia. she likes to be called Ethel.
1968 Dune Buggy sold dec 2024

1974 parts bus
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no lights on dash but the plug wires on #3 and #4 were melted and they had the lowest compression#3 was 35 and #4 was 0

[Abscate]

The engine comes out to be evaluated in that case. I would expect bothe head and piston and cylinder damage.

$1500 for a good used engine installed, 3x that for a rework of current engine, if possible
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Could I just rebuild the top end or would the bottom end need rebuilding too

[Shonandb]

[SGKent]

Turn the key on and see if the alternator/generator warning light comes on. Then check to see if the fan belt came off. If it did, the engine needs to be completely rebuilt. Bearing material can sluff off when an engine gets hot enough to melt wires. If the fan belt is there, with the engine OFF, turn the generator/alternator and see if the belt slips. That will tell you why it melted, unless critters moved into it over the winter and built a nest.
_________________
George Carlin:
"Most people don't know what they're doing, and a lot of them are really good at it."

Skills@EuroCarsPlus:
"never time to do it right but always time to do it twice"

[timvw7476]

[Amskeptic]

[[email protected]]

The problem I have is that I can't find anyone in my area that knows Volkswagen air cooled engines. If anyone knows of someone in west Michigan I would appreciate the help

[mikedjames]

If you are dedicated enough, you will find plenty of basic videos on Youtube showing engine building.

If you were happily hammering a 1600 at 60mph without having given it a basic set of adjustments, it is easy to melt parts of the engine.

Trouble is that if you melt a hole in a piston through the classic "set the timing by ear, it goes like a train" , it sprays melted aluminium dust down into the engine. It then gets circulated round as a powder and gets everywhere. So the engine has to come totally apart for cleaning, to remove all that metal.


But there is nothing stopping anybody from performing a rebuild on a VW engine if you have the space.. or even in the back of the bus..

. That was a rebuild I did a few years back .
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Ancient vehicles and vessels

1974 VW T2 : Devon Eurovette camper with 1641 DP T1 engine, Progressive carb, full flow oil cooler, EDIS crank timed ignition.
Engine 1: 40k miles (rocker shaft clip fell off), Engine 2: 30k miles (rebuild, dropped valve). Engine 3: a JK Preservation Parts "new" engine, aluminium case: 26k miles: new top end.
Gearbox rebuild 2021 by Bears.

1979 Westerly GK24 24 foot racer/cruiser yacht Forethought of Gosport.
1973 wooden Pacer sailing dinghy