1Z/AHU into 78 Bus

markd89

Veteran Member
Joined
Oct 21, 2009
Location
Los Angeles
TDI
1978 VW Bus 1Z TDI
My engine was installed used and now has about 200K miles. During install and over the last few years many little fixes and upgrades have been done. Those things -- flywheel seal, oil cooler assembly, oil pan seal, turbo feed and turbo exit line, CCV puck and CCV lines are all new-ish and not leaking as far as I can tell.

Anything original is a good suspect and 1.9ZOOK pointed out the vacuum pump.

Sure enough, it looks like there may be some oil leaking where it meets the block. It doesn't look like much but I will attend to it. I can see/feel one bolt. Is that it or is there another hidden where I can't see/feel it?

Also, while this likely is A leak, it isn't THE leak. The vaccum pump sits too low to drip oil between the head/block, it must be coming from above. I still plan on replacing the valve cover gasket. This was previously replaced, but maybe it's kinked or something.

Any other old parts I'm neglecting to think of?

The fuel issue is going to wait a few more days. I figure best to do the diesel purge at the same time as changing fuel filters. A new filter will arrive on Wednesday.
 

markd89

Veteran Member
Joined
Oct 21, 2009
Location
Los Angeles
TDI
1978 VW Bus 1Z TDI
Issue #1: Rough idle/missing/smoke. I think this is fixed. I suspect I had a bad tank of B20.

When I filled up this time (with regular diesel), I added some Rislone diesel additive. A couple of days after, I ran the diesel purge per the instructions here on TDIClub. It has been a few days and I haven't seen the symptom again. Injector balance is +/- 0.20 on all injectors.

Issue #2: Oil use. I removed the valve cover today. In the stock Passat, this would be a piece of cake. However, in the bus it was challenging. I did manage to lift the valve cover over the studs, but just barely.

It did look like there was oil leaking past the gasket. The gasket was a little hardened and also may not have been getting properly crushed as the grommets were very hard. Those grommets were probably original to the car. At the time of the swap, when we did the timing belt, I didn't know that they should be changed out also.

A new gasket and new grommets are installed. I cleaned the engine as well as I could. If there's still a leak, I should be able to see it. Fingers crossed that this reduces the oil consumption.
 

markd89

Veteran Member
Joined
Oct 21, 2009
Location
Los Angeles
TDI
1978 VW Bus 1Z TDI
I have new valve cover gasket + grommets installed and no more leaks there.

I also had a little leak where the CCV tube from the block comes up and attaches to the puck.

I had naively replaced the stock "pinch clamp" with a normal hose clamp. I learned that normal hose clamps are good for soft hoses. With a hard pipe, the flat part of the hoseclamp results in a flat part of the tube where it clamps resulting in a square peg - round hole scenario and a leak. Lessen learned.

For now, the leak is cured with RTV and the normal hose clamp. When it's timing belt time, I'll get the right kind of clamp.

Early indications are that oil usage is reduced. I need more time to get full data but it looks like a new engine is not in the cards. Yay!! Thanks to all (as always, esp. Andy) who have helped!

Mark
 

markd89

Veteran Member
Joined
Oct 21, 2009
Location
Los Angeles
TDI
1978 VW Bus 1Z TDI
Oil consumption, stumbly idle and new Malone Tune

Updates:

1. With the new valve cover gasket and the block to CCV tube sealed nicely there is no more oil on the floor :) There is still oil consumption and there is more oil in the catch can, probably because it's not getting blown into the engine compartment anymore. The consumption so far seems acceptable. I will have to add oil every fillup or two, but I'm OK doing that as it saves me an engine rebuild.

2. I still occasionally have the stumble/rough idle on start. It has happened cold and happened warm. My idle, set to 1000 rpms is usually +/- 2. When this is happening, it's +/- 15 and the injector balance shows +2.99 across the board. 5 minutes of driving seems to clear it up and so I'm also not going to worry about that. I suspect there's something in the pump not right, so that'll be a future project at some point.

3. When Mark Malone tuned my bus, we took out fueling from Stage 2 across the board but especially at low RPMs. We did this because of my mistaken belief that too much torque was what had borked the transaxle after the initial build.

It turned out that the rebuilder had failed to replace a bearing and that was the reason for the transaxle sounds. I'm back in-touch with Malone Tuning and hiring them to add back some of that fuel. At the same time, I'm probably going to go MAF-less. Being MAF-less means a simpler system (less parts) and plumbing/space wise, I'll have more options on airboxes.

The project has about 55,000 miles on it. We're coming up on the first TB job. Fingers crossed for no spendy things for another 60,000 miles :)

Mark
 

markd89

Veteran Member
Joined
Oct 21, 2009
Location
Los Angeles
TDI
1978 VW Bus 1Z TDI
Quick updates:

Mark Malone gave me an updated MAF-less tune that has been working nicely. It seems to work just as well as the MAF-tune before. I wanted to go MAF-less just to simplify the intake system a little.

I'm still using too much oil. It's a little less than 2ml/mile now. The likely diagnosis seems to be rings. The catch can, before I removed it, always had a lot of oil (but only a fraction of the 2ml/mile).

This engine had about 130K miles when I got it and has almost 200K now. It's too bad as it starts instantly, gets 30 MPG and performance is more than adequate,

I've been good with maintenance but don't know what the PO did. I could keep adding oil. I could try and replace rings only or rings and head. Right now I am leaning towards starting with a zero mile high-quality rebuilt engine.
 

Inhabor

Member
Joined
Feb 17, 2018
Location
Florida
TDI
Vw bus tdi conversion
What pressure plate and clutch are you using? I'm using a Kennedy stage two pressure plate and Exedy Daikin Heavy Duty Racing Metal Woven Clutch Disc and still slipping.

Sent from my SAMSUNG-SM-G891A using Tapatalk
 

markd89

Veteran Member
Joined
Oct 21, 2009
Location
Los Angeles
TDI
1978 VW Bus 1Z TDI
Darn. I am not sure. I don't remember. I checked all my docs. I found reference to a 025.141.025.LUK plate part but not sure if I used it. Almost positive the clutch is a stock TDI.

Notes that I have on the LUK plate (from someone else): "This is the Premium Heavy Duty clutch pressure plate for Vanagon's made by Luk in Germany. This plate is the favorite of syncro owners and is recommended for use when performing engine conversions. Fits all years and model Vanagons (except the 82 Diesel) from stock GL's to hill climbing Syncros. Stock clutch pressure plate has 1124 lbs pressure while the Luk plate has 1461 lbs pressure - 30% improvement while the clutch pedal pressure that the driver experiences remains the same."

My setup is not setup for all out power. i.e. I have stock turbo, bigger injectors and a tune that's probably stage 1.5ish. There has been much to learn in working out the bugs, but clutch slip has never been an issue.


You might also ask on the Vanagon TDI group.

Good luck... and post some pics!

Mark
 
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markd89

Veteran Member
Joined
Oct 21, 2009
Location
Los Angeles
TDI
1978 VW Bus 1Z TDI
Quick updates:

We just did the timing belt. The TDC marking on the Kennedy plate and flywheel had been a question mark. I can confirm that it is there and works fine. The observation port is about 1/2" diameter. When at TDC, there will be two drilled holes that are visible through the port.

I had strongly considered rebuilding the engine at the same time. I decided to just keep adding oil when it's low. The engine runs strong otherwise. The cost of the project was really getting up there. If I had space to do it all myself and time to do it slowly, I might have done differently. It's going to be 5 years or more before I'm at 60,000 miles again, so maybe then!
 

AndyBees

Top Post Dawg
Joined
May 27, 2003
Location
Southeast Kentucky
TDI
Silver 2003 Jetta TDI, Silver 2000 Jetta TDI (sold), '84 Vanagon with '02 ALH engine
Mark, reading up on your TDI Conversion! How's it doing?

My engine uses a little oil. I usually add about a quart in 10k miles (keeping it topped off to the change interval).

Why are you changing the TB at 60k mile intervals?

I have close to 90k on my project. The pinion has a worn spot on one tooth. I've been building a new transmission. Thus far, I have over $3k in parts and it hasn't been assembled. I hope to finish it this winter. I've had a lot of health issues over the last two years ...... much improved now.
 
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markd89

Veteran Member
Joined
Oct 21, 2009
Location
Los Angeles
TDI
1978 VW Bus 1Z TDI
Hi Andy,

Thanks for posting and great to hear from you. I'm glad you're health is improving now. That comes before all :)

Also sorry to hear about the trans. I feel your pain!

The swap is doing well. I just got back from a 1500 mile trip from CA to AZ and back with no breakdowns. There's 70K+ on the swap now. The TB interval on the MT 1Z/AHU is 60K miles so that's when I did it. I'm sure it would last longer. Supposedly a pulley was made larger or something on the ALH when they went t the 100K interval.

I do have some issues and things I'd like to improve..

1. I put in a new air-oil separator - a Chinese version of the Provent and added a second breather from the oil filler cap. Since doing that, I'm seeing no oil leaking from the valve cover gasket. I'm assuming that the blowby pressure has been relieved. As a result I seem to have less oil "usage" but I'm still adding oil at each fillup (need more data but maybe 1/3 quart every 400 miles). I suspect that my cylinders are out of round. I read that the earlier TDI engines (mine is 97) had something with the position of the rings which cause this and that was corrected in later TDI's. To fix this would involve removing the engine and rebuilding it. This is my only car and I no longer have a place to work on it, plus the cost.. so I just add oil and all is well.

2. The trans sometimes pops out of 2nd gear when unloaded and cold. This is another one where it would take me down and cost a few $k, so I am living with it. With the last rebuild, I went from a .70 to .77 4th. If I had to do it again, I would have kept that .70, or gone with the flipped 5 speed or something else.

3. The oil does get hot on long drives up hills on hot days. I'm not sure if the sensor is before or after the oil cooler but I see 250 *F or higher sometimes. I have the larger oil cooler already. My idea is to put in a sandwich adapter and run an external cooler. Hopefully that will keep me to 210* or so and maybe effect oil usage as well. I have the sandwich adapter. Next, I need to figure out where to put the radiator. The underside of the bus is very full already. I'm thinking of putting it in the cavity above the transaxle but would really like an area with more airflow. I could put it in the engine bay but then I'm going to be heating the intake air.. hmm

Any ideas are welcomed :)
 

AndyBees

Top Post Dawg
Joined
May 27, 2003
Location
Southeast Kentucky
TDI
Silver 2003 Jetta TDI, Silver 2000 Jetta TDI (sold), '84 Vanagon with '02 ALH engine
Mark, I have no suggestions for locating the radiator. A guy I met at the TDI fest in Maine back in 2013 built a frame car powered by an ALH TDI. He engineered and made each piece, literally. Anyway, he said the coolant hoses for Vanagons are really larger than necessary. He used a small hose for coolant return to the engine with a slightly larger hose going up front to the radiator. He said it works well because the water pump is very efficient and moves the coolant faster than most people realized. He drove it from California.

Well, I'm sort of the opinion that we've likely put more miles on our projects than the average. I've not driven mine much over the last three years... likely less than 5k miles. The transmission and some electrical issues is the primary reason.

I purchased a 1975 Transporter three years ago. It needs a lot of work. Very little rust. It did come with a nice stroked dual carb engine that was not installed. The guy needed the cash as his son was beginning college.

Okay, hang in there and keep it on the road...
 
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