50% leakage on #3 a month before my trip

[ac78]

Hi guys and gals!

I am planning a 10 day trip from TN to CO/NM at the end of July. As you know I am experiencing some power loss, backfiring, stumbling but still getting great gas mileage. I did a leak down on Cylinder #3 and at 90 psi, I was only holding 45psi with a really big hiss coming from the tail pipe. The borescope shows difference between the valves too. Cylinder #4 at 90 psi, held about 85. I remember seeing that 10% loss is acceptable. I didn't get to #1 and #2 yet because its been raining but will report later.

I have felt for several weeks now that I am going to need to drop the motor. It happens that I have a perfectly good used head(Cyl1/2) from my old westy rebuild a few years ago. I bought a 10mm 1.0 tap for the temp II sensor and thought I was good to go.

After reviewing the Raby/Bug Me video last night to remember what I was getting into I checked my used head and I do not have a step. When the head was removed, it had a gasket on it. I was hoping to just bolt on my used head and be on my way but do I now need to remove the jugs to put the .006-8 shim in?

I missed hoffman's last run of blueprints so I'll have to wait on a full top end for a bit. Otherwise I do the P & C's too on both sides.

Problem #2 is that I have gravel driveway with no garage... I bought my plywood engine pullin' runway fro Lowes last night. Looks like there are plenty of folks here that have done it the hard way a time or two.

I am still driving it daily and may do just fine on a 3,000 mile trip but just makes me a bit nervous starting out this impaired while picking the hottest part of the summer to drive that far.

Sorry for the novel, just wanted to provide the most info I could. The main question again is:

Because I have no step in the head, do I need to remove the jugs to put the .006-8 shim in since I will not be using the head gasket?

Thanks!
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78 Westy 2.0l hydr. FI

VW Campmobile
For people who believe a family's
car should be it's castle !

[busdaddy]

You'll have to CC the old head as well as the replacement, if they match there's no need for shims, if they don't and the replacement is smaller the jugs have to come off.
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[Tcash]

Compression Ratio

Cylinder head CC kit.

[Wildthings]

You might be able to find someone local who could flycut the ring out of the replacement heads for you.

[SGKent]

You can't use a head like that on a 3,000 mile trip unless you plan to drive below 45 mph the whole way.

If you are leaving in July you are already out of time.
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“Most people don’t know what they’re doing, and a lot of them are really good at it.” - George Carlin

[ac78]

Thanks for the replies all. I am optimistic that I can finish as long as I stay focused on the task at hand. And get started immediately! Last time I had a lot of, why I'm here I might as well replace... That will have to wait til later.
_________________
78 Westy 2.0l hydr. FI

VW Campmobile
For people who believe a family's
car should be it's castle !

[ac78]

Before I started the pull sequence, I thought I would post all four cylinder leak down tests. I did #4 twice with other points of discusssion so it'd be great if you all could spend a few minutes with me and provide some feed back.

I checked with a local shop and they cant fly cut at the moment so I may just do shims. Basically I'm trying to see if I can get away with just replacing the head for my trip. Although I think I can salvage it, we did start discussing plan B. No matter what we are going on vacation.

Thanks in advance!

I actually tested them in order 3,4,1,2 but I posted them 1,2,3,4

Cyl#1 https://youtu.be/luF5AdaF3a8
Cyl#2 https://youtu.be/K1aYoEnz8FM
Cyl#3 https://youtu.be/qkPN_gvwlgU
Cyl#4 https://youtu.be/3mQf7mrHIfU
Cyl#4 https://youtu.be/f3ydVz1MIx0 this was actually first take on 4.
_________________
78 Westy 2.0l hydr. FI

VW Campmobile
For people who believe a family's
car should be it's castle !

[ac78]

I forgot to post this video from my borescope. Cylinder #3- It appears the seat is gone based on how my donor head looks. Both valves should be above the contact surface not below. Am I on the right track there?

https://youtu.be/ChyTmq7WoBw

Thanks for the help!
_________________
78 Westy 2.0l hydr. FI

VW Campmobile
For people who believe a family's
car should be it's castle !

[SGKent]

yes - it ran too hot and the valve spring may be too weak, causing the seat to pound into the head. You'll find the area under the seat probably deformed like someone pushed on softened butter. Need another head. I have some old before Ed sold RIMCO 2 liter ones with 3,500 - 4,000 miles on them that I am taking off to put on some new custom heads Len did for me recently, however I don't know if they will be swapped in time for someone to use them by mid July. They won't be cheap as I probably have $950 in rebuilding them. I'll probably list the set around $800 - $850 but not until I can inspect them thoroughly.
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“Most people don’t know what they’re doing, and a lot of them are really good at it.” - George Carlin

[ac78]

The fact that it is still running as good as it is just shows how resilient these motors are.

I got on the list for Len's next run so I'm going to try to make my spare work until I have more time for both heads, P&C's, general cleaning, tin painting etc.

The other thing that really surprised me was how fine the line is at TDC. You barely crank it and its starts back down.

Thanks!
_________________
78 Westy 2.0l hydr. FI

VW Campmobile
For people who believe a family's
car should be it's castle !

[nerdhotrod]

[chabanais]

[SGKent]

Just opened Len's heads that came in today. Built to the same exacting standards my friends Bill and Wally used to send out of his shop before he retired. (Shop built Cosworth engines that were used at Indy and in FI, also built some score racers for Al Unser Jr) - so when I drool looking at these it isn't because I haven't seen it before. All the guides are the right height - the valves are perfect width on the seat, the custom work exact, I am so so pleased. When you get back be sure to get an order in for a set of these.

[ac78]

They do look sweet! I actually emailed Len today just to make sure someone didn't change their mind and couldn't take them. I am on the list for the next run.

I am also on step 19 of ratwells engine removal page. I should have some teardown tomorrow. My donor head looked better than I remember. Sealing surface is super clean.
My p&cs look pretty good too. Hopefully I won't have to use them but the oil breather and filler tube were quite oily after further inspection.

Ill keep you posted.

Thanks!
_________________
78 Westy 2.0l hydr. FI

VW Campmobile
For people who believe a family's
car should be it's castle !

[ac78]

Update for today. The motor is out and half way torn down on the atv jack. I had hoped to bring a pic of the #3 head but I wasn't able to get it off just yet. I realized you can't take a short cut by leaving the fan housing on. Got to get it up on the engine stand tomorrow and go at it again. Sure would be nice if the tab on tin was just a bit shorter.

I was pleased that it only took an hour of the jack dance to get it dropped.
_________________
78 Westy 2.0l hydr. FI

VW Campmobile
For people who believe a family's
car should be it's castle !

[Tcash]

Good going
Tcash

[Manfred58sc]

Considering the cost of T-4 bottom ends, this is an unwise move. At the very least do a compression test once everything is back together. I have seen the results of slap together T-4 engines and the sadness owners have when they have to do it right (more cost,extensive damage). Good luck.
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Fat chick owner/operator

[ac78]

Update for today. I posted some more videos on YouTube that show both heads and p&cs. The link below is just for the 3/4 side but if you could check out the other 3 vids I posted today that would be awesome. I would like all the feedback I can get for both side if the motor. I apologize for not holding the camera properly in wide-screen.

https://youtu.be/uvGdaCuxY_c

In a nutshell, Both heads are off, 3 of 4 cyl rings are bad and I will be replacing all pistons and cylinders with my Mahle kit that should arrive by Friday. Both heads had head gaskets which surprised me. The 1/2 head a GEX stamp on it. Right now I feel my best route is to get a set of AMC heads and bolt them on out of the box. There are two reasons why:

1. I have no idea when Len's next run will be.
2. I am not considering the west coast alternative based on the relatively recent feedback.

That being said, there seem to be many vendors with AMC 78 oval port heads but there is a $150 price swing for what seems to be the exact same thing on two different part numbers 039101351K and 022 101 061 L . What Gives?

I still plan on getting 2 more heads when Len does his next run and I'll just store those away for another day.

Any feedback is appreciated. Thx!
_________________
78 Westy 2.0l hydr. FI

VW Campmobile
For people who believe a family's
car should be it's castle !

[SGKent]

[nerdhotrod]