When we tuned up the valve gaps I noticed that one of my exhaust ports studs was fixed using a heli-coil. Of course that coil needed to be replace because it pulled out, then when tightening the other side of the same port I noticed the hole the stud was in was cracked, and of course it broke. I tired JB weld but that didn't work.

So my question is... can this problem be fixed, or should the heads be replaced (new or used?), or is there an upgraded head?

I'm assuming the engine will need to be pulled out to take the heads off.

Have you looked at the Time-sert thread repair process? It has much better success than the heli-coil especially on exhaust. The insert is larger than the coil ones so depending on your extent of damage it may not be possible but it is something to look at before pulling the head.

One: Why would you ever think JB Weld would fix that? Is their advertising THAT good?

Two: A timesert fits in the same thapped hole as a Helicoil. It's NOT bigger than a Helicoil. If the boss is cracked, it's cracked, and no insert is gonna fix that. The heads will have to be welded properly, and the odds are the cracks are a LOT more numerous and extensive than you think.

Three: Yes, the engine has to come out to remove the heads.

A bit of advice. If you're going to have the heads welded, use a specialist shop with a LOT of T4 head experience. You could be looking at 1500-2K with parts.

The Cap'n

Sorry Cap'n I thought the OD of the Time-sert was larger. I guess I am just remembering the shoulder cut being lager than the insert.

Actually I was thinking of replacing the heads with used or new. From what I've seen a set of used heads goes for around $300 and new ones around $800. Pulling the engine out and putting heads on is not a problem. My father worked on these engines back when they were still making them.

Any other places to pick up new heads besides aapistons and autoatlanta?

P.S. I know JB weld was a crazy idea, but I was hoping to keep driving until I put the car in storage for the winter.

I have a set of 1.8L heads in decent condition.
If you are interested, I'll pull them out & get some inspection pics.

Stu

When I had HAM redo my heads, he would only take one, the other was really damaged from the valve seat. Anyway, he has a stock pile of used 1.8 and he re-did one of his along with my decent one.

Stu might set you right up tho.

That's what you get when you deal with an experienced T4 head rebuilder .................

The Cap'n

Www.aircooled.net has them.

400 bucks each..cheaper than fixing your.

Rich

Note that the new AMC heads from Spain have decent castings, but not so great hardware. The general procedure with them is to replace pretty much everything but the basic casting when using them. I don't remember if the seats and guides were part of the stuff that should be replaced, but I wouldn't be surprised if they are.

--DD

Just curious.

Have there been documented cases of failures of the new heads, bolted on right out of the box?

Rich

Not sure if the hardware is that bad, but I think the valves and ports are sized for the bus engine rather than the 914 version, meaning it will run but run out of steam at the top end.

Not sure which ones you are looking at but the prices on that page are for a pair. Not each.

Too cheap??

No. Its for a pair. Read closer.

1.8 liter 914 motor uses the same valve sizes and the same heads as the 1.8 liter vw motor.

The difference is in the oil dipstick location.

The only motor that was different is the 2.0 liter motor and the difference was limited to the heads that Porsche put larger valve into for the 914.

So, these AMC castings are bolt on replacements.

I believe some engine builders and machine shops do not like the hardware used in these heads, I have heard that before.

I have not heard of any failures of these heads, so it may not be the top of the line hardware, but for 400 bucks per head, its still a bargain.

Many people buy these heads, remove all the hardware, and build up racing heads from these just because they are new castings...so the alloy has no heat cycles...thus it will take the abuse longer without a failure.

For 400 bucks, it would cost at least that to fix a cracked head...and that does not include buying new hardware, new valves, a valve job, new guides, all of it..

Still a great deal.

rich

I don't know. Len Hoffman was one person I recall saying that the included hardware wasn't up to snuff. He may have documented cases, or he may have simply looked at what was on the heads and decided it was unsuitable. You'd have to ask him.

--DD

Just wanted to clarify that.
It's one persons opinion....however correct he may be, not arguing that point...

I have not heard of any bad things...

Countless documented cases. Have one in the shop right now. Intake seat fell out at 30K miles.
Documented failures in order of most seen.
Retainers pulled through causing valve-piston collision.

Keeper grooves hammered out so bad the end of the valve failed causing valve-piston collision

Seriously hammered ex seats to the point that the adjuster ran out of adjustment

Wildly excessive guide wear.

Broken intake valve guide. The portion that's exposed in the port.

Great castings, shitty parts.

Yes, look no further than thesamba to see them. I have been bitten by them as well, having lost a retainer on a stock engine using a stock cam in a bus application. The retainers are junk and the keepers pull through them. Thats among the random deficiencies with every other aspect of their factory hardware.

I don't even consider using more than just the head castings from these.

I'm glad I started this topic... great info. I still think the AMC heads are each not per pair.

You are absolutely right with that thinking.

1.8 AMC heads have not been available for several years. Might be some still in existing inventory, but they haven't been produced in years.

took me a couple days to dig them out & clean them enough to get pics of the important bits.

They look fine to my untrained eye:
one two side
http://s366.photobucket.com/user/stuartjgr...rt=3&page=1

three four side:
http://s366.photobucket.com/user/stuartjgr...rt=3&page=1

Let me know if you cant get to the photos.
If not, I'll start a for sale thread in the classifieds & post all the pics.

One cyl clearly had something in the cylinder as you can see where it beat up the head a bit, but thats about it for issues.

Stu

I rechecked the page. Some are per pair and some are each. Maybe by brand. Didn't check.

I was able to see the pics. Sent you a PM.

hine62

So I did a quick check on shipping.
If I put both heads in a 24" X24" X 16" box at 30 lbs, UPS is ~$80.
USPS is almost double that.

Does anyone on the forum have a trick for shipping heads?
Maybe cheaper separately?

I can beat the ebay deal if I find a good price on shipping.

Stu

Greyhound freight?
That's how the good Dr was shipping trannies and I know others have used it for larger items.

They fit in large flat rate box! $15 x2 = 30 much cheaper. I just did this.

Post office? UPS office?

Post office.

On the USPS website I only see flat rate boxes up to 12 1/4" x 12 1/4" x 6".
Is that what you used?

Doesnt seem like enough padding to fit a head in that box...

It was very tight. I added a couple of layers of cardboard on to and bottom. Resulted in a slit expansion of the box but it shipped fine.

Stu thanks for doing this! You can PM me the final cost when you get a chance.

hine62

Sorry I have been a little distracted by the flooding surrounding me :-0

The "safe" shipping (big box w/ lots of packing) would be ~$80 while MrBlizzards suggestion would be ~$30 but hardly any protection.

That makes me worry with these heads having the cooling fins.
One drop and a head is toast and I know better than to put "Fragile handle with care" on the label. That gives them incentive to knock it around...

I guess I can just insure the heads for enough to buy a brand new pair and risk it.

The $80 option is good for me. Better safe than sorry later.

No hurry on this stu. I hope you and your family are safe. PM me when you're ready.

hine62