4-Cam Head Removal.

[Alfisto Steve]

With cams out or lobes set so valves are fully closed my head shop has a vacuum bench set up to see if valves seated and will hold a vacuum.

Mr. T. pretty easy to see bent valves by chucking them up in an electric drill motor.

[john.harrill]

Yeah, it probably doesn't take much to mess up the valve's "contact patch" with the seat.

Any thoughts on the health of the guides? Previous to this, I never had any oil consumption problems.

[Alfisto Steve]

If valves not bent much guides probably OK. Prices for 24v intake guides very expensive.

[MrT]

I can only say that the shop that tended my heads reported that the guides were healthy, and that if they'd been replaced, it wouldn't have been an improvement. (I supplied all valve guides). Maybe they weren't tooled for it, or maybe the guides looked great at 75k miles.

[john.harrill]

I'm running the numbers on the parts required to rebuild the heads: It looks like it will be roughly $2000, without valve guides or labor.

I would farm-out the valve work. Everything else, I can do.

I spoke with the mechanic (Il Dottore, in Raleigh, NC) who has serviced the car in the past about the wisdom of re-building. He does quality work and I respect his opinion greatly. He believes that despite the depressed values for the 24V cars, their relative rarity makes them worth keeping intact.

The cars is in good shape otherwise; The normal quirks are evident, like Klingon-language climate control, balky sunroof, airbag light, and an appetite for front strut bearings. The body has a few stone chips but is completely rust free and the paint is very good. The interior shows some cracking of the front seats (Burgundy leather. Kinda rare) but the carpet is almost unworn.

Am I talking myself into something here?

[goats]

Its summer, lazy evenings, if you can work at your own pace why not? I suspect you will find some pleasure in doing this work and will have a genuine sense of accomplishment after its done.

How else are you going to replace a very nice and fun car for, lets say, 3 grand? you can't.

As long as you are not stressed to get it back on the road, time-wise, I say make it your summer project and go for it! A handful of hours every week and by fall you are back in the saddle -- plus you have a car that is relatively bullet-proof for the next 30K miles (till the next tbelt interval!)

bob

[Alfisto Steve]

John send me a PM with your email and I will send your email to Jim in C-ville, VA.

He did heads on his 24v and had a bunch of bent valves. We got parts from Difatta not sure how much he ended up spending on parts.

We also just did a parts list for timing belt, water pump with belts and idler pulley for guy in Austin. No bent valves as he is doing preventive maintenance

[john.harrill]

The '78 spider has new tires and the speedometer is fixed, so back to the 164.

Removed the false firewall, driver's side fender liners, and transmission mount. This freed up alot more access to the rear head exhaust manifold nuts. There is one that won't budge (always), so it's soaked with PB Blaster.

Question: how does the rear engine mount come off?

BTW, I looked at a nice 164S on Saturday. Clutch hydrolics have failed and the owner is on another continent, but otherwise......

[velocedoc]

I will jump in here on this about bent valves. I owned for several years a Honda CRXSi. A car I should have never sold. Why I sold it was because the seats were a killer on a trip, but now that I commute 22 miles to work, it would have been a blast to rocket down the freeway. I am digressing...When I bought the car it ran great. Just had a fresh headgasket/timing belt/water pump installed and I bought it from a local Dodge used car lot. The more miles I put on the car, the worse it started to run. Finally it just refused to go up a hill with out alot of effort. I ran a compression test and it wasn't pretty. I pulled the head and a local machine shop that came highly recommended pulled the head down. All of the valves were bent just enough to barely seal. Someone had mistimed and spun the engine over, kissing all of the valves to the pistons. The only way we could tell was to chuck the valves in a valve grinder and touch the stone to the face. There was roughly a 75% contact area on the seat. New valves fixed the problem and lightened my wallet. I put 100,000 miles on the motor and got alot of smiles back for th effort. The dealer took the car in trade as the car had just had the work done to on it. After I had put so many miles on the car it was up to me to eat the valve job.
The only way you can tell which valves are toast is as I described above. At this point with the heads off, I would just put in all new valves. You might want to check the valve lifters while you have the heads apart just as a precaution.
One question I have is it going to be an issue to put those studs back in the block?

[john.harrill]

Quote:

Originally Posted by velocedoc I will jump in here on this about bent valves. I owned for several years a Honda CRXSi. A car I should have never sold. Why I sold it was because the seats were a killer on a trip, but now that I commute 22 miles to work, it would have been a blast to rocket down the freeway. I am digressing...When I bought the car it ran great. Just had a fresh headgasket/timing belt/water pump installed and I bought it from a local Dodge used car lot. The more miles I put on the car, the worse it started to run. Finally it just refused to go up a hill with out alot of effort. I ran a compression test and it wasn't pretty. I pulled the head and a local machine shop that came highly recommended pulled the head down. All of the valves were bent just enough to barely seal. Someone had mistimed and spun the engine over, kissing all of the valves to the pistons. The only way we could tell was to chuck the valves in a valve grinder and touch the stone to the face. There was roughly a 75% contact area on the seat. New valves fixed the problem and lightened my wallet. I put 100,000 miles on the motor and got alot of smiles back for th effort. The dealer took the car in trade as the car had just had the work done to on it. After I had put so many miles on the car it was up to me to eat the valve job. The only way you can tell which valves are toast is as I described above. At this point with the heads off, I would just put in all new valves. You might want to check the valve lifters while you have the heads apart just as a precaution. One question I have is it going to be an issue to put those studs back in the block?

[john.harrill]

Ok.
I had one nut left where the manifold attaches to the head and I rounded it off. It is on the rear head, middle pipe, top stud. I had previously sprayed copious amounts of PB Blaster on it and let it soak.

Any suggestions?

[BlackAlfa]

I guess heat it with a torch is somewhat out of a question! One option that comes to mind is to detach the manifold from the downpipe (from under the car). But this would make taking the head out even harder if at all possible. For extensive work like this, I would be tempted to drop the engine and subframe down (since I've done it before), slide the whole thing out and work on it while it sits on the subframe.

[MrT]

Get a hacksaw blade out and saw it off flush with the manifold? That should free up the manifold to come off, and you can always replace the stud. They're not anything special, as far as I can remember. 8mm studs are plentiful in the hardware stores I frequent, and these aren't any special length. If it were the bolt (the 12V cars have paired stud/bolt at each exhaust port), then its length might give you some aches in pulling the manifold far enough off to clear between false firewall and head. Otherwise, sacrifice the stud. It isn't worth the time it would take to save it.

Or get a cutting torch and melt the nut off. It will come off before the stud gets good and hot. Cutting torches are one of the most amazing tools I have ever seen. I've seen bearing races cut off like butter without even discoloring the shaft they were on. If it were my finger in the hole instead of a steel shaft, I think I'd not be happy, but gosh they cut quickly.

Or use a file or nut splitter and cut the nut off. If you were careful, you might not even scratch the stud threads. But the hacksaw is the route I think I'd use. I've used it on stuck exhaust system bolts many times without regrets. Is there room for an angle grinder? belt-sander?

Michael

[Del]

Don't forget that if valves are new, the guides and seals must be new as well, or the repair will not turn out right.

[Alfisto Steve]

Quote:

Originally Posted by Del Don't forget that if valves are new, the guides and seals must be new as well, or the repair will not turn out right.