1975 FI Knocking

[mamiyapentax]

Hello Samba, a mechanic told me my engine sounds like a bearing has come loose in the crank case and is "knocking." Previously the top half of the motor was rebuilt with new pistons and heads. Apparently this is an expensive repair that will require a rebuild of the crank. The body of the VW is in great shape and deserves to be back on the road again but as what cost is ideal? One mechanic told me I need an entire new short block.

1975 Type 2 Bay Window
Fule Injection

[kooper271]

If you end up buying a rebuilt engine:

Since you are near the east cost, I would try and contact Gary Leblanc from Suburban Engine in Massachusetts about a rebuilt engine.

If you were on or near the west coast, my choice would be headflow masters.

Either should be in the neighborhood of $3-$4k

Regardless of who you go with, I would try and get a new cam instead of a reground cam. A lot of people go with a web cam, but the $99 cam from european motorworks is good and cheap.

[williamM]

There are lots of things go "Knock" in that motor- your new heads could hsve dropped a pushrod or rocker stud-- the oil pump idle pin can move into the cam gear,-- many an exhaust leak has sounded like a knock-

Would like to hear an audio of that if you can- how many miles?

Few more details on the motor- like the Id number- how many rebuilds its suffered.

If you have or can get an boroscope from harbor freight (think it's $89. with coupons- and take a look in each hole for signs of disaster.

would cut the oil filter open for signs- if no fragments or silver oil- would definitely look further.
_________________
some days I get up and just sit and think. Some days I just sit.

opinion untempered by fact is ignorance.

Don't step in any!

[lil-jinx]

If a little thing like an engine rebuild makes you think of selling,then the love affair is over.Sell!
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https://www.thesamba.com/vw/forum/viewtopic.php?t=620186
https://www.thesamba.com/vw/forum/viewtopic.php?t=668799
1974 Bay Westfalia. she likes to be called Ethel.
1968 Dune Buggy
1974 parts bus
A smart man learns from his mistakes,a very smart man learns from other's mistakes.

[williamM]

[Wildthings]

Type 4 engines are not prone to bearing problems, their bottom ends tend to last until the cam is no longer serviceable. You might pull the oil pump and make sure the idler shaft hasn't backed our and it hitting the rivets on the cam and that the cam gear is nice and tight on the shaft.

[mamiyapentax]

I will get out my microphones and record the sounds of the engine.

This happened when I was riding on I-87 and pushing the motor. No smoke but a loud rattling noise came out of no where and I lost power. The engine was always strong driving up and down I-95 to Miami.

Anyway most of the replies are outside my realm of understanding but I am willing to learn. I do NOT see metal in the oil.

[timvw7476]

For starters, check under the valve covers, I had a rocker assembly
back off & shut down a cylinder, thought I'd blown something, just a
couple loose nuts. Start with the simple to inspect stuff.