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valve adjustment

I recently bought a 73 914-4 1.7L that had been sitting in storage for 10 years (advertised by a friend - HA - as 5 years) and having had the gas drained - HA - the stuff stinks. Anyway, I am learning my way around the minimally rusted hunk (really!!) and the first thing besides trailering it 1500miles was to adjust the valves. I also in the process of rebuilding the carbs, cleaning the gas tank and so much more.

The issue I have for the forum is about adjusting the valves. I have followed Wayne R. Dempsey's nicely written article on the valve adjustment and have found a problem. Piston 1 and 2 were no problem, when I got to 3 I found that when I backed out the adjusting screw the valve spring followed. This has made guessing the clearance (.006) a total mystery.

So, have I screwed up locating TDC or is the engine totally busted? Any thoughts?

Old 12-12-2001, 03:47 PM
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David,

If you return to the article and read the amended portion by Tim, it desribes the method I have used repeatedly to adjust the valves. The nice thing about it is that it doesn't rely on locating timing marks that may not be correct.

I had similar problems when trying to use the TDC for each cylinder method. I even placed the marks on the flywheel, etc. What screwed me up later was that the timing needed changed, and this affected the marks, which screwed up locating TDC for all cyls.

If you use the second method described in the article, you'll not go back.

Another tip: I found that adjusting valves so that the gauge has a noticable-to-heavy drag on it when setting the clearance improves the results. If you settle for less drag the valves tend to be noisy.

Good luck,
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Old 12-12-2001, 05:46 PM
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re-valve adjustment

I appreciate the suggestions about the valve adjustment. I have had trouble figuring out which are the exhaust and intake valves. I think the outside ones are the exhaust.

I have some WV friends who think the valve is busted (the valve spring moving when I untighten the adjusting screw).

Can you suggest a way to see if the valve is broken without dropping the engine out of the car?

Thanks again

David
Old 12-13-2001, 09:58 AM
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If the valve stem has broken, it seems you could unbolt the rocker assembly, pull it away, and the valve spring and stem should slide out.
Old 12-13-2001, 10:46 AM
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Here is what through me for a loop

I caught my myself chasing my tail in circles one day. Could not get the adjustment right on one set of valves. Only got worse when I pulled the rocker and the push rods slipped out of thier pocket in the lifter. Ended up with the swivel foot adjuster tight up against the rocker. After a serious pucker (oh no I broke something) and three beers to think about what was going on I realized the error of my way.
Old 12-13-2001, 12:02 PM
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Joe Ricard,
Thanks for the message of hope. Any suggestions on how to proceed? I am a loss right now on what to do next. If I can't get the valves adjusted it seems like a bit of a dead end.

Thanks

David
Old 12-14-2001, 12:27 AM
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for your sake, i hope i am not understanding your post, but... correct me if i am not understanding.... you make me think that as your back off the adjusting screw, the valve tip follows the adjusting screw, stays in contact with the screw and also "backs out" ???? what this makes me think is, especially since you refer to the dreaded #3 cylinder, is a dropped valve seat. like i said, i hope for your sake that it is not a dropped valve seat. but, if the valve stays in contact with the adjusting screw, then maybe, there is no seat in the head to "stop" the valve head. maybe that is why the car sat for 5 or 10 years. this basically happened to my 81 vanagon. if you can turn the engine over, try a compression check on the #3 cylinder and see if you get any compression at all. i think 0 compression would make me think dropped seat.
Old 12-14-2001, 05:54 AM
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jmcleod
Many thanks for the suggestion. I will give it a test and see what happens. Right now the carbs are in peices, but I can turn the engine over with the battery and starter. That should help test the compression.

David
Old 12-14-2001, 06:38 AM
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Folks it gets more interesting. I went and bought a gauge for testing the compression (nice device, by the way!). Cylinder 1 and 2 were the ones I felt I had adjusted properly had 100 psi. The offending cylinder 3 had 25-30 psi and number 4 had zero. So 3 has more than I and jmcleod thought. But what's up with 4?

Forgive the stupid questions. Do you have to drain the oil out to adjust the valves? I put oil in when I turned the engine over, but had the engine drained prior. The engine seems to turn over pretty easy. Certainly the rings are probably a bit sticky after sitting for 10 years.

To 3D914: I tried the method you suggesting but kept getting lost. I am not real sure which are the exhaust valves or which are the intake valves. It certainly seems to be a better method.

I appreciate the shop 101 from you all. I may end up going back to woodworking (something I know a lot about) and fixing my house which is in almost as bad shape as the car.

Thanks again

David
Old 12-14-2001, 12:24 PM
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Intake valves are the center ones, exhaust valves are the outer ones.

Not sure what's going on with your valves or your compression. Are you sure you had the motor set to the right place??

--DD
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Old 12-14-2001, 05:13 PM
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At this stage, I am pretty sure the exhaust valves for 3 and 4 are shot. I went through the process of adjusting the valves and the exhaust valves for 3 and 4 do what jmcleod described. After testing the compression again 3 and 4 have basically no compression.

I think the sucker is toast

Anybody need some part? I've got 2 very nice dellorto carbs.

David
Old 12-15-2001, 07:28 AM
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Don't part it out!!!!!!

Any type-4 1.7L head will fit it (well actually the very early ones had different pushrod tube opening so check that out first).

I'd say $25-$50 far a usable used head $100+ for a rebuilt. They are very common. Maybe $200+ to have a local mechanic put it on, you can do it yourself, it isn't difficult, and we'll walk you through it.
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Old 12-15-2001, 12:23 PM
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Cool I agree I agree I agree

Although I know squat about the 914, I've been trying to talk David into digging deeper and atleast find out what the problem is. If its just a head, will the head from a 1.7 engine out of a bus motor work? I know its pretty much like a bus engine, but Im not sure about the ports.

If we pull the engine, has anyone pulled an engine from a bus and can tell me what is different? I assume the tranny will have to come out, unlike a bus. Any other major differences?

Up to you, David.

David
Old 12-15-2001, 04:51 PM
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Look at the tech articles on this site, very good engine drop article. Yes it is easier to remove the trans and engine as one. Once it is out there are a number of seals and such that sould be replaced as the car sat so long.

The T-IV 1.7L heads are all the same, except for the pushrod tube thing. The 1.8L 914 head is the same as the carbed bus 1.8L head, the 914 2.0L head is unique. The late bus heads 80-83 I think have different exhaust ports, but all the earlier ones are the same as the oval ports on the 914.
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Old 12-16-2001, 08:55 AM
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AHHHHHH!!!!!!!!

Alright. My curiosity and Bugjunction's (David) help we will find out what is wrong with this thing. The good news is that adjusting the valves brought the compression up on 1 and 2 to 100psi. I guess I should have guessed that 3 and 4 would be trouble. The carb on the same side was frozen from rust. I have managed to get it freed up and working fine.

I contacted the original owner again and was told that he put the car in storage working. He had the twin Dellorto's put on a month prior and then the shop that did the work went bust. The car never worked right with the Dellorto's. I think I do know why. The original gaskets were what look like rubber antivibration gaskets and they were installed all chewed up. There could not have been a good seal between the carbs and the intake manifold. Hopefully the carb rebuild kits will get here in time to test the engine if we figure out what is wrong with it. My guess is that something in the 3 and 4 side rusted/fused. When I finally got the engine to turn over (lots of PB Blaster and probably to much force) something probably bent.

JP Noonan encouragement is appreciated. We Floridians need to stick together. JP you up in Gainesville occasionally?

David
Old 12-16-2001, 04:28 PM
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Just drop that sucker

RUST IS BAD! Actually wouldn't cost much except some sweat Equity. My 15 yr old pulled my motor in 3 hours. Almost back together and will reinstall after XMAS.
Just to pull the offending head is easy. It is the "since I'm In here: that will cost. Good luck and wea are all standing by to help.
Old 12-17-2001, 03:34 PM
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The Good, the Bad and the Ugly

Well, the engine is out and the head is off. Thats the GOOD part. The BAD and UGLY part is, we found the head and cylinders to be crusted over with some rusty crap. Other than that, all looks ok so far. I didnt see any reason why the valve could not be adjusted or why a quart of oil would dump out when he took the valve cover off. Davids assumption was, the car sat outside and dripped water in thru the engine lid and down into the carb. This would explain why the carb on that side was kinda crusty and why the inside of the head was nasty.

Atleast it didnt drop a valve and put a hole in the piston.

If the valve seat was bad, wouldnt the valve be lower than the rest of them?

Actually, the engine didnt look that bad.

The saga continues

David
Old 12-23-2001, 07:18 AM
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The next question I have is the 1.7 engine worth rebuilding. If I have to spend the money to rebuild and engine, it would be nicer to have a bigger engine, 2.0 at least. At least with the 2.0 sometime in the future it could be made even larger. Is it reasonable to look for a 2.0 bus engine and how large a can of worms does this open?

Thanks

David
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Old 12-23-2001, 07:50 AM
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A dropped valve seat can result in a valve tip that sits at a different height than the rest. But it won't always. Check around the seat (combustion chamber side) for damage. I had a seat that would pop out and back in again--but it left damage in the head right by the seat.

Also try holding the head up to the light to see if you can see any light past the edges of the valves. If so, that is a pretty major compression leak.

--DD
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Old 12-23-2001, 12:40 PM
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Hint from years of rebuilding air-cooled diesels: with the valves installed with springs, etc., we used to pour a little diesel fuel into the ports of the valve. If it leaks by the valve into the combustion area then you don't have a good seal.

Old 12-23-2001, 05:49 PM
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