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vwwestyman Mon Feb 20, 2017 8:10 pm

I resurrected my Thing a year and a half ago, after it sat for about 25 years.

Around town it is great. Keeps up pretty well, all that.

On the highway, though, it is an exercise either in frustration or patience, not sure which. Maybe both. 55 is doable, but more or less pushing it. 60 is rare.

Last fall after a valve adjustment and warming up the motor, I did a compression test. #1 was at 85 lbs, #3 was 110, the other were right around 100.

As far as I know, the transmission is still stock. Tires are General Grabber AT2, 27x8.5 R14. No top, no windows, sometimes no doors.

The engine does leak quite a bit of oil.

I'm thinking about pulling it and resealing it.

I don't think I'll have time/money in the right combination to do a total rebuild before Thing weather comes along again. I'm sure I could get it resealed in a weekend if I put my nose to the grindstone.

So I guess maybe the question is, I know the compression is a little low, especially on #1, but is that enough to make a significant difference in power/top speed? Or are those things more affected by things such as my tire choice and/or lacking a top, etc (wind resistance)?

OR, am I wasting my time by tearing it down far enough to reseal it without rebuilding this motor?

I believe that Type 1 pushrod tube seals cannot be replaced without pulling the heads. Can the heads be pulled enough to replace the pushrod seals without removing the factory dual mufflers? They are in fairly decent shape, but I think they may crumble if I try to remove them.

williamM Mon Feb 20, 2017 9:18 pm

will your motor rev up going down the highway-- I ask because there was a RGB model which over the years may have been mated with the wrong trans to get over gearing or under gearing -- which would limit your top speed.

Heads-- Because of the tin removal, heater boxes, PR tube accessibility- Just drop the engine, put it on a stand and be comfortable assessing the leakage.

vwwestyman Mon Feb 20, 2017 9:39 pm

williamM wrote: will your motor rev up going down the highway-- I ask because there was a RGB model which over the years may have been mated with the wrong trans to get over gearing or under gearing -- which would limit your top speed.

Heads-- Because of the tin removal, heater boxes, PR tube accessibility- Just drop the engine, put it on a stand and be comfortable assessing the leakage.

How do you mean rev up? If I'm driving 55-60ish and hit the gas, not a lot happens.

I was thinking I'd buy a whole seal kit, pull the engine, and replace all the seals. I have the '73 dual muffler setup. No heat exchangers.

Wildthings Tue Feb 21, 2017 2:38 am

Sure that your timing advance mechanisms are working correctly? With the hoses removed for the distributor you want to see 28-32 BTDC at 3500+ rpms. If you time your engine by the book and the retard can is bad your timing if going to be way way off and your engine horribly sluggish.

You could also time your engine statically to 7.5 BTDC if you don't have a strobe style timing light available.

vwwestyman Tue Feb 21, 2017 5:44 am

I would say I'm pretty sure that the timing is advancing.

The original dual vacuum distributor was seized up and not advancing, so I swapped in a single vacuum version that seemed to be free. I'm pretty sure I set it to about 30 degrees advanced... Do you know how far over from the TDC mark is that?

Wildthings Tue Feb 21, 2017 8:17 am

vwwestyman wrote: I would say I'm pretty sure that the timing is advancing.

The original dual vacuum distributor was seized up and not advancing, so I swapped in a single vacuum version that seemed to be free. I'm pretty sure I set it to about 30 degrees advanced... Do you know how far over from the TDC mark is that?

1 13/16" to the right of the original TDC mark

vwwestyman Tue Feb 21, 2017 8:22 am

Thank you. I'll give it another shot as soon as I get a chance.

So with the compression numbers I have, do you think the engine is relatively healthy, though maybe "middle aged?"

williamM Tue Feb 21, 2017 8:27 am

Have you pulled the spark plugs after a bit of a 55 mph drive to see what is going on with the mixture- You may have an air bleed plugged up and it's running rich. Can go the other way too- but usually "romping on it" will put a load of accelerator pump fuel and you should expirence a sudden power- if its running rich you will get a bog as the rich engine clears the injection.

Try blowing back thru that long fuel line to the tank- you might have a restriction there that limits the top end.

Do like the timing for this too.

prom8n Sat Feb 25, 2017 4:26 pm

Brand new, things would top out at 65 on a good day. Aerodynamics of a dumpster, 60 hp, they're not freeway flyers.

Compression is directly related to horsepower. If #1 is at 85, it's too low. It'll run but it's like having one tire almost flat while the others are doing all the work. Causes undue wear and stress on the engine. Minimum acceptable compression is 100 psi, but honestly you want consistency on all 4 cylinders over high compression.

Could be the head needs to be re-torqued for #1, or try squirting some oil into that cylinder and re-testing compression. If it comes up, good indication the rings are worn. No change would say the valves need a re-grind.

Does it pull good at lower speeds? Accelerate away from the stoplight ok? If you're weak on high speed power (which you don't have much of anyway), it could easily be a carb / fuel problem, or a timing issue. If you went to a single-vac distributor, those usually should time out at 0 deg. with the vacuum line off.

One other check: try moving the crank pulley in and out to see what your end-play is. Should be max .006 thousandths, so if you can see or hear it move. it's pretty worn out.

Please post results.

Paul R.

"Horsepower is how hard you hit the wall. Torque is how far you take the wall with you."

Wildthings Sat Feb 25, 2017 8:45 pm

prom8n wrote: Brand new, things would top out at 65 on a good day. Aerodynamics of a dumpster, 60 hp, they're not freeway flyers.

Compression is directly related to horsepower. If #1 is at 85, it's too low. It'll run but it's like having one tire almost flat while the others are doing all the work. Causes undue wear and stress on the engine. Minimum acceptable compression is 100 psi, but honestly you want consistency on all 4 cylinders over high compression.

Could be the head needs to be re-torqued for #1, or try squirting some oil into that cylinder and re-testing compression. If it comes up, good indication the rings are worn. No change would say the valves need a re-grind.

Does it pull good at lower speeds? Accelerate away from the stoplight ok? If you're weak on high speed power (which you don't have much of anyway), it could easily be a carb / fuel problem, or a timing issue. If you went to a single-vac distributor, those usually should time out at 0 deg. with the vacuum line off.

One other check: try moving the crank pulley in and out to see what your end-play is. Should be max .006 thousandths, so if you can see or hear it move. it's pretty worn out.

Please post results.

Paul R.

"Horsepower is how hard you hit the wall. Torque is how far you take the wall with you."

Back in the mid seventies my then girl friend thought nothing of running my Thing at 80 mph all day long.

vwwestyman Mon Feb 27, 2017 11:39 am

Wildthings wrote:
Back in the mid seventies my then girl friend thought nothing of running my Thing at 80 mph all day long.

Seems like there is a Thats What She Said joke in there! LOL

I don't remember if that 85 number was with oil or not.

It does, to me, feel like it accelerates from a stop light just fine.

Can anyone tell me if it is possible to remove the heads (to replace the pushrod tube gaskets) and leave the '73 style dual exhaust on the heads? It seems if I can separate from the carb heat riser I could do that. Am I crazy about that?

prom8n Wed Mar 01, 2017 11:25 am

Yerf. Well, Remove the valve covers, undo the rocker arm shaft nuts (Save those copper washers!), pull and label all the pushrods so they go back in the same place.

You can now pry out the pushrod tubes without removing the head, but you're most likely gonna damage them beyond reuse.

You can't move the heads without accessing the top bolts which are under your cooling shrouds, and to get at those you'll need to pull the generator / fan shroud, most of the tinware, the heat riser, etc. Good sized job with the engine out, next to impossible with the engine still in the car.

OR... you could get a set of those spring loaded adjustable push rod tubes and insert those instead. Pricey, but you could install new seals without touching the heads.

http://www.jbugs.com/product/4108.html

Hope this helps.

Paul R.

vwwestyman Wed Mar 01, 2017 1:06 pm

Assuming I do this job (and I really need to, it leaks quite a lot), I would be pulling the engine and the fan shroud anyway to 1) clean it up and 2) replace the oil cooler seals.

So then it shouldn't be much further to pop the heads off. I'm just hoping with the dual mufflers, I can leave them attached to the heads because I think to remove them it may cause some damage to them. The metal is intact but somewhat thin and I'd rather not have to buy new mufflers.

williamM Wed Mar 01, 2017 2:30 pm

are your mufflers thru the bumper or bug style? Should think the RR engine plan the best- you can examine the trans seal/ clutch and case plugs for other possibilities.

vwwestyman Wed Mar 01, 2017 2:34 pm

They are the original mufflers that were installed in 1973 I'm sure. So they are two completely separate mufflers and the tail pipes do exit through the bumper.

williamM Wed Mar 01, 2017 6:20 pm

while shopping round

i saw some mufflers at "the thing shop" which were quite reasonable.- like less than $150. :?:

depending on your use- it might be time to do it.

once down to the oil cooler- your a few screws away from total exposure.

vwwestyman Wed Mar 01, 2017 6:53 pm

You sure? I do not see any mufflers on their exhaust page, and searching "muffler" yields no results either.

Wildthings Wed Mar 01, 2017 7:00 pm

vwwestyman wrote: They are the original mufflers that were installed in 1973 I'm sure. So they are two completely separate mufflers and the tail pipes do exit through the bumper.

The original mufflers on my first '73 where shot when I bought it in the fall of 1977, so I would doubt yours could possibly be original. :cry:

vwwestyman Wed Mar 01, 2017 7:03 pm

Wildthings wrote: vwwestyman wrote: They are the original mufflers that were installed in 1973 I'm sure. So they are two completely separate mufflers and the tail pipes do exit through the bumper.

The original mufflers on my first '73 where shot when I bought it in the fall of 1977, so I would doubt yours could possibly be original. :cry:

It came from Dallas, and sat in a barn for 25 years. So it seems possible to me. I think there is a VW logo stamped on them, but I'd have to check for sure.

williamM Wed Mar 01, 2017 8:27 pm

williamM wrote: while shopping round

i saw some mufflers at "the thing shop" which were quite reasonable.- like less than $150. :?:

depending on your use- it might be time to do it.

once down to the oil cooler- your a few screws away from total exposure.


Just went there and not a muffler in sight- was round "black friday" I saw them- must have been a lost leader- Should have bought one then suppose.



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