1.9 DF bearing condition + other

[krankenwagen]

Hi there,

About one year ago I purchased a 1991 2WD Vanagon (or Transporter T3 as we call it here in Europe)

The original engine that came with the vehicle was a 1.9L petrol engine. The previous owner told that he ignored the oil pressure warnings and continued to drive, to the point that the crankshaft blew through the engine block. Vehicle was then sold to another owner, who installed a "2.1L SS engine" as he told me when I purchased the van from him. It was equipped with a 2.1 style cooling, and carburetor system, but with a help of a really helpful friend we converted it to a Digifant fuel injection system.

Last summer the dreaded oil pressure demon started harassing me with this new donor engine. I stopped driving the van, replaced sensors and checked the wiring. Then I installed a mechanical oil pressure gauge to find out that the pressure was 1.4 bar @ 2000 RPM, and it could drop below 0.9 at some situations. At idle it was around 0.5 bar. These measurements were red from a warm engine. Using Valvoline 20W-50 oil.

Instead of just slapping a bigger oil pump, decided to crack open the case this winter and check & replace all of the bearings before more damage would be made.

My first surprise was when I removed the oil pump. It already had been replaced with a bigger Schadek 30 mm pump. The pump cover had some scarring marks that could be felt with a finger. Oil pickup dish was clean and no noticeable amount of foreign particles were there.

Second surprise was that the engine's internal bearings looked "kinda ok", but I'm not completely sure of this because I've never seen a bad bearing IRL. What do you think?

Third surprise was to me that the engine block is not a 2.1L SS, but a 1.9 DF. It was revealed after I cleaned all the grime from the base of the breather tower.

Pistons and cylinder sleeves are not original. They are Mahle. Notice the amount of rust in the cooling portion. Wrong mixture of coolant? I noticed that the van was kinda slow to heat up.

https://web.tecalliance.net/mahle-catal ... mber:10686

As for the crankshaft, I am not sure if it is a 1.9 or a 2.1 version. Haven't been able to measure it's stroke, and there is no part number anywhere to be seen.

How does this engine look internally and could the bearings in this condition cause big amount of oil pressure drop being in this condition?

My next move would be to take the crank and case halves to a machine shop to have them checked and atleast crank's bearing surfaces polished.

A Big Thanks in advance.

[Ian Godfrey]

At a glance those bearings don't look too bad.
3 things have to be in balance, the size of the oil pump, the bearing clearance and the oil viscosity.
Either buy some good measuring tools or get a good machine shop to measure your crank and and the new bearing clearance in the case after it is torqued to spec. Also the rod clearance needs the same care.
I mostly built type 1 engines and the recipe I go for is: 26mm pump, 2 - 2.5 thou rod clearance, 2.5 - 3 main bearing clearance (1.5 - 2 on the nose bearing), 10 - 40 oil. Some times you need to mix and match bearings to get the clearance you want. A Vanagon engine will be not much different.
It may be worth getting someone like Rocky Jennings to do the measuring and machining and set up the short block for you to build out.
good luck

[AMBROSIA]

If it's a 1.9 case the 2.1 crank won't fit without some clearance work to the roof which yours does not have.
Your oil pressure issue is likely down to the aftermarket pump.
Aftermarket pumps are sized for T1 engines and although will fit in a WBX case are a loose fit.
As the oil thins out the oil will bleed out around the pump case back into the sump.
Marco Mansi sells o-ringed pumps that resolve this issue.
Alternatively any good machine shop can machine 2 grooves either side of the inlet/outlet holes and then you can source suitable o-rings.
There is also the option to anodize the pump body to take some of the clearance up but this is not the better solution.

The other thing to check is the oil pickup tube is not damaged where it slides into the case.
I use some thread lock in this area when refitting to ensure a leak free seal.

Looking at the head studs I would say this engine has had the proper coolant most of it's life.
Lastly, someone has fitted a cylinder upside down (Arrow should point to the flywheel) so it was previously built by someone either inexperienced or worse negligent.

[krankenwagen]

If it's a 1.9 case the 2.1 crank won't fit without some clearance work to the roof which yours does not have.
Your oil pressure issue is likely down to the aftermarket pump.
Aftermarket pumps are sized for T1 engines and although will fit in a WBX case are a loose fit.
As the oil thins out the oil will bleed out around the pump case back into the sump.
Marco Mansi sells o-ringed pumps that resolve this issue.
Alternatively any good machine shop can machine 2 grooves either side of the inlet/outlet holes and then you can source suitable o-rings.
There is also the option to anodize the pump body to take some of the clearance up but this is not the better solution.

The other thing to check is the oil pickup tube is not damaged where it slides into the case.
I use some thread lock in this area when refitting to ensure a leak free seal.

Looking at the head studs I would say this engine has had the proper coolant most of it's life.
Lastly, someone has fitted a cylinder upside down (Arrow should point to the flywheel) so it was previously built by someone either inexperienced or worse negligent.

Thank you very much for your comprehensive answer! This was just what I was looking for!

The oil pump was a pretty loose fit, as I could just slide it out of it's housing easily with moderate force. IIRC the pump should be a very tight fit, and could be removed (only) with a puller tool. I have already bought the Marco Mansi's pump and regarding the whole rebuild, I'm thinking I just could have replaced it, but I took the longer route

The heads were in this condition when I removed them:



Also the 2-piece main bearing had some strange marks on it's sides. Any thoughts on this?



Regarding those wrong way installed pistons, could there be any long term harm installing them the right way this time? I have no idea what kind of a person built this engine in the past, but this was a good notice.

[Bruce.m]

Piston have the pin offset by a tiny amount to reduce noise especially when cold. Doubt it will cause any damage though, being upside down.

[AMBROSIA]

Regarding the bearing marks my only guess would be to direct the oil that bleeds out.
This method can be employed on the rods to direct oil into the piston undersides for extra cooling.
Not sure why this would be done on a main bearing though, but it does look deliberate.
Seeing the jugs like that would indicate use of the wrong coolant or perhaps even straight water for a while.