Replacing clutch,flywheel, and rear main seal on my 1970 bus

[addison5429]

Hello all!
This week I will be pulling the engine on my 1970 bus with 1600cc engine to replace the clutch, flywheel, throwout bearing, and rear main seal. Earlier this summer I was driving home and the bus felt like it was loosing power, the engine would rev but felt like the wheels were getting no power. The bus started smoking so I pulled off the road and oil was all over the underside of the engine and so I had it towed home. Im assuming replacing these along with an oil and filter change.

My question is what else should I look for when I go to change out the flywheel etc. any tips things I need to look for? thank you!
_________________
[url=http://www.vw-mplate.com/mplate2-9652.png]Click to view image[/URL]

[wihr]

Many years ago I had a similar problem with my 1970. I changed the main bearing only to later find that there was a crack in the case behind the flywheel. Check your cases too.
_________________
WIHR

1970 Campmobile "Van Ordinaire"
2009 Lincoln Town Car "Behemoth"
1969 Lambretta 150 DL "Nina"
1962 Matchless G 12 CS 650cc

[SGKent]

There are two seals to be concerned about - the main seal on the engine and the main seal on the trans. A burned piston can raise blowby to where it comes out seals even though they are not bad. A slipping clutch can overheat the main seal. VW cases do crack in the back behind number 3 as I recall. Clean it really well on the back with soap and water, let it dry and flex the back of the case with your hands. If there are cracks you will see a fine line weep oil.

crack in rectangular box right down the middle

_________________
“Most people don’t know what they’re doing, and a lot of them are really good at it.” - George Carlin

[airschooled]

All good ideas.

Off the top of my head, I do all of this annually when I remove the engine, unless it's an emergency pull before a big trip.

- Check and adjust end play if needed. (Requires new flywheel seal.)
- Inspect muffler/heat exchanger flanges for leaks and repair if needed.
- Torque exhaust hardware to 12-14 ft/lbs. Factory wants 18, but if you're diligent here, you're better off with constant retorques with lighter settings. 18 is for setting it at the factory and not seeing it for 6,000 miles. 12-14 if you can recheck it a couple times in the first week, then a month, then every 6 months.
- Replace dual port intake boots, if applicable. Check 18 ft/lb torque on intake manifold pieces.
- Inspect oil cooler base for leaks. Seals are easy to do with the engine out, impossible otherwise.
- Inspect oil cooler for proper Hoover bit and foam seal.
- Check torque on fan nut, 36mm socket, it's somewhere above 40 ft/lbs. Check Bentley for exact setting.
- Inspect rubber engine mounts on mustache bar.
- Disassemble and lubricate clutch throw-out assembly. Replace worn or cracked bushings.
- Inspect transaxle input shaft seal, replace if weeping. Some people do it as a matter of practice.
- Inspect clutch cable bowden tube for cracks.
- Feel throw-out bearing (clutch release bearing) for ANY grit or roughness. Replace if found in the slightest way.
- If using the early style throw-out bearing, obtain and install the better style clips with the loop. The U shaped ones are less good.

Because of your smoked clutch scenario, I would add:
- Clean and cross-hatch sand flywheel. Experience will tell you if you need it resurfaced. When in doubt, have it resurfaced but make sure the shop is NOT ALLOWED TO LIGHTEN IT.
- Same with the pressure plate, a light cross-hatch to remove any glaze, but if it's not smooth a new one may be in order.
- Work the clutch mechanism by hand and study how it works until you really understand how the throw-out/release mechanism functions. Operate the cable by hand without the engine installed, and feel how easy it is. Once the engine is back in, make sure your clutch cable free play is about an inch. The free play should be just as easy, and when you encounter resistance, you will then "know" that your throw-out bearing is contacting the pressure plate and beginning to release the clutch. We DO NOT WANT this while driving. Ask me how I know……
- Examine your driving habits to make sure that you're never using the clutch pedal as a foot rest, never revving the engine too much starting from a stop, and always waiting to press the accelerator until the clutch pedal is released during shifts. I see no reason that a clutch disc on a 57hp economy car shouldn't outlast the human race.

Please let us know if any of these (or anything else) needs further explanation.

I'm sure there will be more great ideas tossed around too,
Robbie
_________________
Learn how your vintage VW works. And why it doesn't!
One-on-one tech help for your Volkswagen:
www.airschooled.com

[addison5429]

Here is the earlier topic on the details about what happened this summer.
http://www.thesamba.com/vw/forum/viewtopic.php?t=605150

I bought all the stuff to fix the clutch today will pull the engine tonight and work on it
_________________
[url=http://www.vw-mplate.com/mplate2-9652.png]Click to view image[/URL]

[airschooled]

[SGKent]

in case anyone is wondering why Robbie doesn't want the flywheel lightened.

The mass in the flywheel and size is engineered to make the flywheel and crank flex in a certain spot on the crank when it flexes. (Essentially the center of mass). If the flywheel is lightened too much it moves the center of mass on the crank. The spot VW chose is the thickest and strongest part of the crank. If it moves into a weak spot, like where a rod journal joins one of the main journals, the crankshaft will snap.
_________________
“Most people don’t know what they’re doing, and a lot of them are really good at it.” - George Carlin

[Tcash]

Just a reminder, don't forget to disconnect the throttle cable!

[addison5429]

@tcash yes last time I took out the engine I forgot the accelerator cable lol
_________________
[url=http://www.vw-mplate.com/mplate2-9652.png]Click to view image[/URL]

[airschooled]

[Tcash]

Ask me how I new.

[addison5429]

Ok I do have a question I meant to ask earlier but will now before I tear into it. The clutch peddle, from the time I bought it, had A very high clutch point. Is this normal?
_________________
[url=http://www.vw-mplate.com/mplate2-9652.png]Click to view image[/URL]

[Tcash]

Link

[addison5429]

Ok got the engine out and think the clutch was burnt up . All sorts of black powerdy stuff in th flywheel. Question what size is the flywheel bolt?
_________________
[url=http://www.vw-mplate.com/mplate2-9652.png]Click to view image[/URL]

[airschooled]

[dasdachshund]

[dasdachshund]

[addison5429]

Ok got the gland off it came off pretty easy with just a breaker bar so I feel there is a bigger issue. Then the flywheel didnt want to slide off so I finally got it off but three of the studs came off is this ok? It looks like they may have fused together or domething. Two were stuck in the flywheel and one just came off when I was looking at the two left on the engine
_________________
[url=http://www.vw-mplate.com/mplate2-9652.png]Click to view image[/URL]

[busdaddy]

The dowels can stay in either part, what's important is how tight they all fit in the holes.
_________________
Rust NEVER sleeps and stock never goes out of style.

Please don't PM technical questions, ask your problem in public so everyone can play along. If you think it's too stupid post it here
Stop dead photo links! Post your photos to The Samba Gallery!

Слава Україні!

[addison5429]

Well I had to beat the two out of the old flywheel
_________________
[url=http://www.vw-mplate.com/mplate2-9652.png]Click to view image[/URL]