Whats w this motor?

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SlowLane
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Re: Whats w this motor?

Post by SlowLane » Tue Mar 29, 2016 9:47 am

I fear that we are re-treading old ground here. We've established that this engine, regardless of the case prefix, is a rebuild, most likely to Vanagon 2.0L specs, so treating it as if it were a 1700 for tuning purposes is just going the wrong way.

We've also established that there is visible valve recession on one of the #1 cylinder valves. To me this is the big red warning flag. It's almost a certainty that the valve seat has parted company with the head and is simply rattling around loose in its pocket. I strongly recommend that you stop running this engine and prepare yourself for a forensic tear-down. So far you have been lucky that the valve seat hasn't slipped out of its pocket and gotten wedged cock-eyed beneath the valve. This could lead to further damage to valve train and piston, possibly even the con rod and crank.

At the bare minimum, you are looking at head replacement or repair. Depending on your budget and patience, you have several options there:
  1. Get your existing heads re-worked by a local shop. Given the relative rarity of type IV engines, you are unlikely to find a shop that will be able to do a satisfactory job and will likely be right back where you are now in a few months time.
  2. Install new AMC heads. There has been much discussion on TheSamba and elsewhere about how crappy the valve hardware is on the stock AMC heads and how it should all be discarded and replaced right out of the box. I dunno, I have been running unmodified AMC heads on my van since 2005 and have had zero problems with them. I saw head temperatures reaching up to 448 degrees last summer and they are still working fine. YMMV.
  3. Send your existing heads off to Len Hoffman at HAM. Len is generally recognized as the pre-eminent type IV head guru. He may decide that they are not worth rebuilding.
  4. Have Len re-work some fresh AMC heads for you. Though expensive, this would give you the most peace of mind in the long run.
Heads aside, you ought to perform a careful tear-down of the engine, assessing wear to each component as you go to determine exactly what needs to be replaced and what can be re-used. Don't try this with the engine installed in the van. The contortions that you'll need to go through working on the engine in the van aren't conducive to maintaining the thoughtful state of mind you will require. A few things to consider:
  • Check ring fit to pistons and piston ring groove condition. You may only need to re-ring your existing pistons and de-glaze the cylinder walls with a light honing.
  • Strongly recommend getting your rods checked and re-furbished. New bushings pressed in and reamed on the small ends, Big ends measured and re-sized if necessary. The rods can be removed and installed from the crankshaft without splitting the case, though it is easier working on a bare crank, especially for when you use PlastiGage to measure rod bearing clearance.
  • Pull the lifters and examine them for pitting or unusual wear on the face (keep them in order so that you can put them back in their original bores. An old egg-crate is handy for this). Examine the camshaft lobes through the lifter bores for unusual wear patterns.
  • Check the crankshaft end-play as described previously. Additionally, do a check for excessive thrust bearing clearance that can give you a misleading reading on your end-play measurement and cause you to dial in too small an end play.
I also think you should stop worrying about the low idle vacuum until you have grokked the entirety of your engine. For all we know, it could be the camshaft selection which is giving you a low reading. Or it could be the limping #1 cylinder.

You could also go whole-hog and order one of Jake Raby's Camper Special kits for your rebuild. But if you do, then you've agreed to be part of the Raby ecosystem and will need to follow his philosophy and instructions to the letter. If you don't and go back to him with problems, he'll probably just tell you to go piss up a rope.
'81 Canadian Westfalia (2.0L, manual), now Californiated

"They say a little knowledge is a dangerous thing, but it is not one half so bad as a lot of ignorance."
- Terry Pratchett

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Bleyseng
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Re: Whats w this motor?

Post by Bleyseng » Tue Mar 29, 2016 1:48 pm

Len does not rework old used heads anymore. 99% of bus heads are so heat cycled that even after going thru them the material under the valve seats is crap.
Geoff
77 Sage Green Westy- CS 2.0L-160,000 miles
70 Ghia vert, black, stock 1600SP,- 139,000 miles,
76 914 2.1L-Nepal Orange- 160,000+ miles
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AZ Landshaper
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Re: Whats w this motor?

Post by AZ Landshaper » Tue Mar 29, 2016 4:00 pm

I'm gonna eval my head(s) and then probably go w new AMC heads if something else doesn't show up and I may or may not have someone rework them. If nothing else I'd make sure the cut is three angles and surface areas at seats are sufficient to seal up for years to come. I'm not gonna spend 2200 on heads from Raby. Id like to get the most for my buck and that is considering that I drive a VW van about 5k miles a year max these days. If I can squeak twenty thousand miles out of this setup I intend to. I'll mak a more informed decision once the head is off.

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SlowLane
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Re: Whats w this motor?

Post by SlowLane » Tue Mar 29, 2016 7:48 pm

AZ Landshaper wrote:I'm gonna eval my head(s) and then probably go w new AMC heads if something else doesn't show up and I may or may not have someone rework them. If nothing else I'd make sure the cut is three angles and surface areas at seats are sufficient to seal up for years to come. I'm not gonna spend 2200 on heads from Raby. Id like to get the most for my buck and that is considering that I drive a VW van about 5k miles a year max these days. If I can squeak twenty thousand miles out of this setup I intend to. I'll mak a more informed decision once the head is off.
Sounds like a reasonable strategy. Just remember that when you're deep into the engine and the "as long as" impulse nags at you.

My AMC heads didn't have a three angle grind, but the seat width was correct. Since the real reason for a three angle grind is to get the seat width nailed, as opposed to the general opinion that it is for "flow", I didn't worry about it much.

A very worthwhile investment of your time is to clean up the molding flash on your new heads. There are also some sharp corners in the pushrod tube socket areas that can be smoothed out to avoid cutting/pinching the pushrod tube seals during installation.
Bleyseng wrote:Len does not rework old used heads anymore. 99% of bus heads are so heat cycled that even after going thru them the material under the valve seats is crap.
Len pretty clearly details what he will accept and what he will not on his Used Type 4 Cylinder Head Policy page.
'81 Canadian Westfalia (2.0L, manual), now Californiated

"They say a little knowledge is a dangerous thing, but it is not one half so bad as a lot of ignorance."
- Terry Pratchett

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AZ Landshaper
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Re: Whats w this motor?

Post by AZ Landshaper » Wed Mar 30, 2016 9:16 am

Got the head off. I'm a bit surprised I don't see more wear. Probably good that I don't. How does one post a pic here? I've got a few of the suspect.

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AZ Landshaper
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Re: Whats w this motor?

Post by AZ Landshaper » Wed Mar 30, 2016 9:20 am

Yup deff lost the seat?
Sunk? whatever!

When I look I don't see much but when I run my finger across the two intake valves, the one for no 1 is deff lower by a margin. Lower than the exhausts too.
Oh well. Now on to the next step.

Anyone know a good source for AMC heads?

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airkooledchris
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Re: Whats w this motor?

Post by airkooledchris » Wed Mar 30, 2016 10:11 am

http://www.ebay.com/itm/251467109001

This is the best deal ive seen online in recent history, but def do a little searching to be sure.
1979 California Transporter

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the miz
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Re: Whats w this motor?

Post by the miz » Wed Mar 30, 2016 10:30 am

AZ Landshaper wrote:Got the head off. I'm a bit surprised I don't see more wear. Probably good that I don't. How does one post a pic here? I've got a few of the suspect.
Try opening a photobucket.com account, dump your photos into there. Once you have that set up it is easy to use the image function on this forum...if I recall correctly, you click the "direct" function on the photobucket page that contains your photo and it copies the link to your clipboard...just hit img on your forum post and then paste in the link.
...at least that's how I do it... :sunny:
Miz
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AZ Landshaper
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Re: Whats w this motor?

Post by AZ Landshaper » Wed Mar 30, 2016 11:10 am

Link to pics of the suspect appear to be too large. There's also the issue w my computer literacy. Lol
Image

Tap pic to see rest of album

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Bleyseng
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Re: Whats w this motor?

Post by Bleyseng » Thu Mar 31, 2016 5:07 am

SlowLane wrote:
AZ Landshaper wrote:I'm gonna eval my head(s) and then probably go w new AMC heads if something else doesn't show up and I may or may not have someone rework them. If nothing else I'd make sure the cut is three angles and surface areas at seats are sufficient to seal up for years to come. I'm not gonna spend 2200 on heads from Raby. Id like to get the most for my buck and that is considering that I drive a VW van about 5k miles a year max these days. If I can squeak twenty thousand miles out of this setup I intend to. I'll mak a more informed decision once the head is off.
Sounds like a reasonable strategy. Just remember that when you're deep into the engine and the "as long as" impulse nags at you.

My AMC heads didn't have a three angle grind, but the seat width was correct. Since the real reason for a three angle grind is to get the seat width nailed, as opposed to the general opinion that it is for "flow", I didn't worry about it much.

A very worthwhile investment of your time is to clean up the molding flash on your new heads. There are also some sharp corners in the pushrod tube socket areas that can be smoothed out to avoid cutting/pinching the pushrod tube seals during installation.
Bleyseng wrote:Len does not rework old used heads anymore. 99% of bus heads are so heat cycled that even after going thru them the material under the valve seats is crap.
Len pretty clearly details what he will accept and what he will not on his Used Type 4 Cylinder Head Policy page.
Len states "We do still work with most models of used Type 4 heads. These include pretty much all models except the O.E. VW 2.0 transporter heads." Old 2.0l bus heads are trash as buy a set of reworked AMC heads.
Geoff
77 Sage Green Westy- CS 2.0L-160,000 miles
70 Ghia vert, black, stock 1600SP,- 139,000 miles,
76 914 2.1L-Nepal Orange- 160,000+ miles
http://bleysengaway.blogspot.com/

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Amskeptic
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Re: Whats w this motor?

Post by Amskeptic » Thu Mar 31, 2016 6:48 pm

AZ Landshaper wrote:Link to pics of the suspect appear to be too large. There's also the issue w my computer literacy. Lol
Fascinating picture with the potential for visual deception.

If you imagine the right side as the foreground, it looks like a recessed valve.

If you view that the left is the actual foreground, it is all looking fine and healthy.
Colin
BobD - 78 Bus . . . 112,730 miles
Chloe - 70 bus . . . 217,593 miles
Naranja - 77 Westy . . . 142,970 miles
Pluck - 1973 Squareback . . . . . . 55,600 miles
Alexus - 91 Lexus LS400 . . . 96,675 miles

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AZ Landshaper
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Re: Whats w this motor?

Post by AZ Landshaper » Fri Apr 01, 2016 6:01 am

Thats about what I see. If Im picking up what your puting down the valve is cattywompus in the seat. NO?? Looks so to me. Just a hair lower on the one side than the other. Im acquiring a set of heads as we speak and will have a machine shop clean them up. My goal is to be back in the saddle by Tax Day so I can blaze by the post office at 5-pm and see the line of US citizens who decided to wait till the last minute to pay off Uncle Sam.

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Amskeptic
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Re: Whats w this motor?

Post by Amskeptic » Fri Apr 01, 2016 9:18 am

AZ Landshaper wrote:Thats about what I see. If Im picking up what your puting down the valve is cattywompus in the seat. NO?? Looks so to me. Just a hair lower on the one side than the other. Im acquiring a set of heads as we speak and will have a machine shop clean them up. My goal is to be back in the saddle by Tax Day so I can blaze by the post office at 5-pm and see the line of US citizens who decided to wait till the last minute to pay off Uncle Sam.
I was speaking of the valve margin/seat profiles.

Otherwise, is that a crack, highlighted with a little white trace, going from one seat to the other?

Have you filled the combustion chamber with some liquid or another (I use gasoline) to see if the valves seal?
Colin
BobD - 78 Bus . . . 112,730 miles
Chloe - 70 bus . . . 217,593 miles
Naranja - 77 Westy . . . 142,970 miles
Pluck - 1973 Squareback . . . . . . 55,600 miles
Alexus - 91 Lexus LS400 . . . 96,675 miles

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SlowLane
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Re: Whats w this motor?

Post by SlowLane » Sat Apr 02, 2016 12:03 am

Oh, hey, AZ. Some of the valve stem ends on that head look pretty rough. That could imply that the corresponding adjusting screws are also chewed up.

Suggest you treat your new heads to a new set of adjusting screws. Don't go cheap on the screws either. Get genuine VW if you can.

The first (cheap) set I put in my rebuilt engine were shedding curls of metal in less than 50 km. They had no heat-treating at all. Bought from a supposedly reputable engine builder, too. :pukeright:

So I bit the bullet and went to the VW dealership to shell out $11 CDN apiece (plus 14% PST/GST) for eight new factory-blessed screws. Totally worth it in the long run.

Since you have hydraulic lifters, don't be tempted to use swivel-foot adjusting screws. They aren't compatible with hydraulic lifters.
'81 Canadian Westfalia (2.0L, manual), now Californiated

"They say a little knowledge is a dangerous thing, but it is not one half so bad as a lot of ignorance."
- Terry Pratchett

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AZ Landshaper
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Re: Whats w this motor?

Post by AZ Landshaper » Sun Apr 03, 2016 2:51 pm

They hold fuel. Seals quite well actually but the valve is deff not straight in the seat and the adjustment screw on intake 1 is sticking out a good 2mm past the others. These heads have been stamped by three manufacturers. Probably pretty used up at this point.

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