Vanagon TDI cooling question

[HBB]

Do you still have the EGR system installed?

[TDI_VT]

This system has always had g12 in it. Never noticed a sludge before.

The egr has been deleted.

Collin
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1986 Vanagon GL white, 1.9 TDI AHU

2007 BMW R1200S More HP then 1.5 vanagons

2015 Jeep Grand Cherokee 4x4 Limited Ecodiesel

1998 VW Jetta TDi RiP, it was an organ donor though....

[TDI_VT]

Well, think I found an issue...

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1986 Vanagon GL white, 1.9 TDI AHU

2007 BMW R1200S More HP then 1.5 vanagons

2015 Jeep Grand Cherokee 4x4 Limited Ecodiesel

1998 VW Jetta TDi RiP, it was an organ donor though....

[TDI_VT]

Also, should I have the block decked? Is that causing my gasket not to seal correctly?

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1986 Vanagon GL white, 1.9 TDI AHU

2007 BMW R1200S More HP then 1.5 vanagons

2015 Jeep Grand Cherokee 4x4 Limited Ecodiesel

1998 VW Jetta TDi RiP, it was an organ donor though....

[vwjetboat]

you need to clean the block deck and then check with a strait edge.. it most likely is ok.. they make many different head gaskets.. have you had head checked and figured out what thickness MLS gasket you should be running ?

[TDI_VT]

Do I need to pull the whole motor to get the block cleaned? Does it look bad enough for that?

I measured, but am not confident In what I had for measurements. I had a 2 hole gasket on there which returned compression numbers of ~300 (at altitude).

The head was resurfaced by frank 06, so confident it's solid.

Thanks
Collin
_________________
1986 Vanagon GL white, 1.9 TDI AHU

2007 BMW R1200S More HP then 1.5 vanagons

2015 Jeep Grand Cherokee 4x4 Limited Ecodiesel

1998 VW Jetta TDi RiP, it was an organ donor though....

[vwjetboat]

you can take a flat file or what ever long as its dead flat.. put a fine sand paper under and gently clean the surface you will soon see if you have issues.. as it should all be nice and shinny and even looking..

dont forget to put rags in cylinders to keep trash out

[MarkWard]

You need to clean the block deck, not the entire block. You should put something in the oil supply hole and the oil return holes to keep stuff from getting in them.

There are a few methods for cleaning the block's deck. You need it clean for the straight edge to sit flat. You check both sides end to end and then diagonally across the block as well. I don't recall the spec, but anything more than .004" is probably not going to seal well. I would also check the head while you have it off. What sort of head fasteners did you use?

Don't get too aggressive on cleaning the block with a 3m pad on a grinder. You can actually add divets to the surface. If you had something flat like a plate of steel, you can cover it with some 320 sandpaper and work it across the deck. Low spots will remain untouched. High spots will have a sheen from the sand paper.

I have not come across a block that had a deck so warped, you could not use it. If the block needs to be decked, it will need to come out and be torn down. A machine shop should jig it up using the main journals to hold it square.

I thought you had a coolant circulation problem not a blown head gasket.
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[TDI_VT]

The original issue was a blown head gasket, and when I put it all back together, I had no coolant circulation and could see tiny bubbles in the coolant expansion tank.
_________________
1986 Vanagon GL white, 1.9 TDI AHU

2007 BMW R1200S More HP then 1.5 vanagons

2015 Jeep Grand Cherokee 4x4 Limited Ecodiesel

1998 VW Jetta TDi RiP, it was an organ donor though....

[MarkWard]

Blown head gasket or not, you still need to sort the circulation problem. Even a blown head gasket won't keep the coolant from circulating.

If the coolant was boiling on the surface the water jacket, that would have put bubbles into the coolant just like a boiling pot of water. The bubbles form on the bottom surface of the pot and float to the surface.

If you took the engine apart originally for a blown head gasket, replaced the head gasket and it blew a second time, sorry to say you missed something.

For the gasket to seal, surfaces need to be bare metal clean and square to each other. If you are using head bolts, you need to verify the bolt holes in the deck of the block are clean and dry. I can see in your picture, coolant laying on top of the pistons. If coolant is in the thread holes, it can hydraulically prevent the bolts from tightening down. I have seen cracked blocks, where someone did not take the time to clean the bolt holes properly. Threads should also be chased so that you get a consistent torque across the block. I'm sure you will figure it out.
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[vwjetboat]

water pump impeller fell off..

[Christopher Schimke]

[vwjetboat]

[TDI_VT]

Thought about that one. Water pump is new, I did check by hand to make sure the pump spins with the pulley. Admittedly, I don't know if there is a slipping issue between the impeller and the pulley under load.
_________________
1986 Vanagon GL white, 1.9 TDI AHU

2007 BMW R1200S More HP then 1.5 vanagons

2015 Jeep Grand Cherokee 4x4 Limited Ecodiesel

1998 VW Jetta TDi RiP, it was an organ donor though....

[TDI_VT]

Also, mark, do you have a good lead on where to get the right size thread chaser?
_________________
1986 Vanagon GL white, 1.9 TDI AHU

2007 BMW R1200S More HP then 1.5 vanagons

2015 Jeep Grand Cherokee 4x4 Limited Ecodiesel

1998 VW Jetta TDi RiP, it was an organ donor though....

[vwjetboat]

without reading the whole thread.. did you pull the bypass hose off the end of the head? the tiny hose ... that clogs up and you need to drill it out

[vwwestyman]

You can create a thread chaser out of one of your spent head bolts. Just use a dremel tool or similar to cut some notches in the threads so that it looks like a thread tap from a tap and die set.

My usual practice for making sure no errant coolant or oil is in the head bolt holes is to attache a piece of hose that'll fit into the bolt holes to my shop vac hose (usually some duct tape is required for this). I'll suck out the holes, then fill them with carb cleaner and suck them out another time or two. Go ahead and chase the threads maybe between a couple rounds of carb cleaner.

I have to say I'm now a fan of the ARP head studs for the TDI motor. (Beware that early on people were using head studs for another motor that were the same dimensions. They didn't have as good of luck, but now ARP makes TDI Specific studs.)

This spring, my TDI had a very tiny head gasket leak that would send a few exhaust bubbles through the bleeder hose. It wasn't enough to cause overheating or anything, but was enough that on a long enough trip (over about a half hour or so) it would start to push coolant out the expansion tank sometimes.

I figured, "what the hell" and gave the ARP bolts a try. They're reuseable so I had nothing to lose other than the hour or two I spent swapping the bolts for studs one by one (so I didn't have to remove the head).

Well, that was in April and I have not had a single tiny bubble go through the bleeder port since. (I have a clear line in that section and have checked multiple times). I've driven it from Kansas to Colorado and up and down passes twice since then.

I'm not saying that the ARP studs will fix every head gasket leak. But I have clear evidence that they are capable of sometimes sealing up a tiny leak and it sure seems like they should help prevent the possibility of leaks down the road. And they are reusable, so by the time you dink around with this a couple times you've paid for them by not having to re-purchase head bolts multiple times. And possibly avoiding having to tear things apart for a head gasket job.
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Dave Cook

President, Wild Westerner Club

1978 Champagne Edition Westy, repowered to '97 Jetta TDI
1973 Wild Westerner
My Thing

[TDI_VT]

@vwjetboat: which bypass?

I have the generic bolts. I'm willing to give arp a try
_________________
1986 Vanagon GL white, 1.9 TDI AHU

2007 BMW R1200S More HP then 1.5 vanagons

2015 Jeep Grand Cherokee 4x4 Limited Ecodiesel

1998 VW Jetta TDi RiP, it was an organ donor though....

[vwjetboat]

[TDI_VT]

Oh your talking the hose that comes off the big hose off the center of the head? The big hose has the coolant temp sensor...and the hose your talking goes to the top of the coolant bottle? I have the vanagon diesel hose setup.
_________________
1986 Vanagon GL white, 1.9 TDI AHU

2007 BMW R1200S More HP then 1.5 vanagons

2015 Jeep Grand Cherokee 4x4 Limited Ecodiesel

1998 VW Jetta TDi RiP, it was an organ donor though....