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simonjb
So I decided to clean up my original engine while I run the car with a modified scat engine.

When I drained the oil I found these....two small pieces and the nut.....(dime for size). So I started to tear down the top end and found one cylinder that looked not so good. The others are the same as the right side. went down further and removed the pistons and am now cleaning them all up. Everything looks ok. I really don’t want to split the case or go any further and from what I see inside all look good. So two questions....

1) any thought on why this cylinder isn’t firing right ?

2) can I use something like gasoline or similar to flush and clean out the inside of the case with the crank and oil pump etc still attached?

3) any reason why I can’t use all the old parts ?

4) any thought on the nut?

Thanks....
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Tbrown4x4
Why did you pull the engine? How long did it sit?

That's a lot of rust to just put everything back together without a trip to the machine shop.

The nut kind of looks like a rod nut, but can you get a boroscope into the case and see if any are missing?

In my eyes, that should be a full tear down and inspection.
jmalone
Tear it down. Several obvious problems and likely more unseen ones! agree.gif
porschetub
Water has entered the motor so you need a top overhaul,the heads will need work also,I flushed out my last crankcase with petrol and was amazed @ the shit that came out and then did a final wash with brakeclean,came out really clean.
You will have limited use of the existing parts unless you rebore the barrels to 96mm with new pistons,unless you can find a good used 94mm barrel and piston for that cylinder you have had water in.
The heads will need rebuilding if they aren't cracked or have bad seats and guides other than that a good used set may be a better option...depends on your funds.
That isn't a rod nut ,appears to be a random someone dropped in there,in the early days I found part of a spring in my 911 conversion motor and none of the wise men on Pelican knew what it was so wasn't worried.
Cairo94507
That nut looks like it is a recent addition to the engine. I see no evidence it ever bounced around in there while the engine ran.

Since I am dreaming and spending your money....if it were me, that engine would come apart and have everything checked. At the bare minimum, have the crank checked and polished, cylinders honed with new bearings, rings, etc. and balance everything. Of course a complete head/valve job. If I had a 4 cylinder car it would be a 2056 with a cam that would work well with the factory FI and then a nice SS exhaust system with heat of course. I would also run a little oil cooler just because it gets hot here in CA. beerchug.gif
simonjb
Thanks all...so I will take the advice and tear it all down - any advice on new Pistons?
Tdskip
Piston/jug sets are pretty cheap, not sure the time/labor/risk of trying to re-use is worth it in this case.
mepstein
QUOTE(Tdskip @ Mar 27 2020, 08:24 PM) *

Piston/jug sets are pretty cheap, not sure the time/labor/risk of trying to re-use is worth it in this case.

Many people reborn the cylinders and get pistons to fit since the original ones were made with good metal and a good machine shop should make the cylinders round which isn’t always the case with replacement cylinders.

But before you purchase anything, break the engine down, clean the parts and assess what you have.
simonjb
So I'm now in full tear down mode. This is what I found - some pieces missing off the camshaft gear. I assume this needs to be replaced? The part number of the cam looks like 021 109 101K? and the gear is 021 109 111B

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Superhawk996
Abosolutely replace it. That engine has seen some abuse. Inspect carefully.
simonjb
Any ideas on where to find new camshafts?
Tbrown4x4
Webb Cam, CP1, LNengineering, air-cooled.net...………...
Superhawk996
@ simonjb

Don't take this the wrong way, I have no idea about your background and experience with engine rebuilds. But, based on your questions, I would suggest a few things:

1) Read the factory manuals. Get familiar with this engine, its parts, and the components.

http://p914-6info.net/Manuals.htm

2) buy the CD from Jake Raby on how to rebuild type 4 VW engines. They are different than than typical VW type 1 engine. It appears to me from your heads and pistons that you have a 2.0L which is just another more unique variant of the typical type 4 than you might othewise find in 914's (1.7L/1.8L) or a VW bus. Sample of video below. The cost of the CD will be saved x10 in mistakes later. Plus it's entertaining to see Jake so young! We were all much younger back then! biggrin.gif


https://www.youtube.com/watch?v=-OOwrsOmXJc


3) Before you go buy a cam you need to know what you want to do with the engine. Will it be stock Fuel Injection (FI) or will you be running carbs? The cam selection will depend on the answer. I can't see much from the photo of the stock cam but from what little I can see, it almost appears that that cam doesn't even have much wear on it. Can you post a photo of just the cam lobes at the most narrow end (in side view)? That is where the typical wear occurs. You typically get a noticeable U shaped trough at the center of the lobe where the two lifters share the same portion of the cam lobe.

As a community, the members here are awesome & are here to help, but, if you're not already familiar with Porsche 914's and Type 4 engines #1 and #2 are priceless resources.
BeatNavy
^^ All good points.

I'd add the Wilson book as a good resource as well: https://www.amazon.com/Rebuild-Volkswagen-a...s/dp/0895862255

Try to develop a plan before you start buying parts. Completely stock, induction system, what compression ratio, etc. These are things I eventually figured out as I went along, but an experienced builder goes into a rebuild knowing them ahead of time.
Superhawk996
QUOTE(BeatNavy @ Apr 7 2020, 09:23 AM) *

^^ All good points.

I'd add the Wilson book as a good resource as well: https://www.amazon.com/Rebuild-Volkswagen-a...s/dp/0895862255

Try to develop a plan before you start buying parts. Completely stock, induction system, what compression ratio, etc. These are things I eventually figured out as I went along, but an experienced builder goes into a rebuild knowing them ahead of time.



agree.gif

I don't know how I forgot that one! That book is a must have. That book actually is what I learned with before there was ever an internet or Raby videos!

I still have my original, and it's falling to pieces. This past Christmas my wife bought me a new copy! santa_smiley.gif Best wife ever!
simonjb
Thanks all. I have the book and the Raby DVD number 8. It seems finding a stock OEM 2.0 cam with gear is almost impossible. My cam shaft is in good shape, but the gear is chipped . The gear is riveted to the shaft - and I see that some places sell the gear only - with bolts. Is this an ok way to go? Or should I try to find a cam with the gear attached?
simonjb
anyone?
Superhawk996
QUOTE(simonjb @ Apr 12 2020, 11:47 AM) *

anyone?


@simonjb

If you're staying with stock cam profile, Web Cam has the stock profile available and of course you'll need to buy the seperate bolt on cam gear. Of course they have other cam profiles available for use with carbs too.

As you've noted the stock cam is rivited to the stock cam gear. As a generalizaion, I'm pretty sure a competent machine shop could drill and tap the stock cam to work with an aftermarket bolt on gear. However, given the risk and expense in doing this, it would make more sense just to buy the Web Cam & bolt on gear for around $300 ish.

The main reason I was curious about your stock cam was that they are usually worn out and need replacment anyway. If the stock cam is not worn, then that is a reasonable indicator of how much mileage was on the engine before this cam gear chipping occured.

Becuase your cam gear is chipped you need to pay special attention to the crank side mating gear. It may be damaged too from whatever caused the cam gear to chip. Pay special attention to this engine. When you've had a gear chip like that something (other engine schrapnel?) got in between the teeth and caused the chip.

Likewise, once I've had scrapnel in an engine like you have had:

1) I consider the oil cooler to be scrap. There is no way to ensure that some particle of debris isn't stuck in the oil cooler waiting to come out only after you've freshly rebuilt your engine.

2) Disassemble the oil pump - schrapnel will score up the pump gears and/or the aluminum pump body damaging it's ability to deliver proper oil pressure. You don't want to rebuild the rest of the engine with a damaged oil pump.

3) All oil galley plugs need to be pulled to ensure there isn't debris stuck at the end of a galley just waiting to come out into you're freshly rebuilt engine.
BeatNavy
I kind of think that's the way they are all sold now. Probably because there are so many different grinds now that it doesn't make sense to slap gears on all of them. Box up the grind the customer wants, throw in the one and only timing gear, and let the customer assemble.

It's also probably fairly rare to want to replace your gear but not the cam. You could drill out the rivets and tap them for bolts so you could buy just the gear. But I wouldn't necessarily trust myself doing that correctly.
simonjb
Thanks guys. Replace both it is....
BeatNavy
Also, when you do assemble and install the cam, pay special attention to those bolts to make sure you have clearance against the case. I'm not sure how often it happens, but I had a small clearance issue that required some minor grinding on my part to make sure everything rotated cleanly.

Good luck. Getting it back together and hearing it fire up (and not blow up) is very satisfying beerchug.gif
simonjb
So I am now starting the rebuild after the tear down, cleaning, new parts, testing, etc....One question, I am putting in new barrels, pistons and cam, pins, bearings etc, but keeping the original crank which was tested and is in good shape. In addition, all 4 crank rods checked out. However, I assume I should replace the 4 round bushings at the small end of the rods. From what I have read, this isn't a do-it-yourself home job, but instead should be done by local machine shop. Am I correct?


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Mark Henry
Ohhh man...that engine stand is a recipe for disaster. blink.gif

Those cheap engine stands are crap, over on the samba a guy sells reasonable priced 3 arm stands.
And I hope that bench is screwed to the wall. As soon as you add the weight of the crank and P&C's the whole thing, bench and all, will fall on it's nose.
unsure.gif
simonjb
QUOTE(Mark Henry @ May 31 2020, 06:14 PM) *

Ohhh man...that engine stand is a recipe for disaster. blink.gif

Those cheap engine stands are crap, over on the samba a guy sells reasonable priced 3 arm stands.
And I hope that bench is screwed to the wall. As soon as you add the weight of the crank and P&C's the whole thing, bench and all, will fall on it's nose.
unsure.gif


No, it won’t. There is an Alfa Romeo engine inside the crate. And I’m only using it to do one half.
porschetub
QUOTE(simonjb @ Jun 1 2020, 11:42 AM) *

So I am now starting the rebuild after the tear down, cleaning, new parts, testing, etc....One question, I am putting in new barrels, pistons and cam, pins, bearings etc, but keeping the original crank which was tested and is in good shape. In addition, all 4 crank rods checked out. However, I assume I should replace the 4 round bushings at the small end of the rods. From what I have read, this isn't a do-it-yourself home job, but instead should be done by local machine shop. Am I correct?


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Yep not DIY,I have found these stand up fairly well but with piston pins worn on cold start you hear a noise like ticking it soon go's away after the engine warms up.
The new lubed piston pins should be a firm push to pass through the rods.
Best to replace,EMW have speced rebushed rods for a great price ,last time I checked it was $55 for 4...excellent value from a good shop and most likely cheaper than the small end bushes to fit and ream somewhere else.
iankarr
Have you had the case checked and / or decked? 50 years on, there's a good case that the registers need to be trued up. Usually on the 3/4 side. If the registers are off, the head won't seal to the cylinders properly and you'll have to tear the whole thing down to fix it. I'm going through this right now on a 2.0 engine. #4 register is .020 out. Ugh.
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