Converting a 1.9 head to instal on a 1.6 mech. block

[saurkraut]

Well, it was a productive week end.  I got the 1.9 head built up.  Pulled the old head, drilled the steam holes in the block, and got the 1.9 head on.

Here is the block after the steam holes were drilled.  The bores look really good, with no ridge at the top yet.  Synthetic oil is good stuff.  Some of the pistons showed a tiny bit of heat damage in a few small areas along the edges.  They were allot better than I expected, since I'm running 25+ PSI boost, and have been occasionally approacing 1500° pre-turbo EGT.  But since I didn't see any bore scuffing, I'm leaving them in.  I may dial back my fuel a bit though. :wink:



I also measured the piston protrusion.  It calls for a one notch.  I've been running a 3 notch.  I guess that explains the rough starts with over 400 PSI cylinder pressure.  Anyone remember the squish band discussion?  I  also wonder if I had the right gasket in there, I wouldn't have the slight heat damage at the edge of the pistons, as having the right squish also contributes to piston cooling when its in close proximity to the much cooler head (quench).

I bought a sheet of viton rubber and cut a circular 'gasket' for the extra oil drain hole.  The 1 notch gasket .0602" thick, and the viton is .0625" thick. I hope I got enough compression of the rubber plug to seal it. I put a little Dirco on both sides of the round rubber plug for added insureance.

And here is the G60 valve cover, and the original tin timing belt cover.  Good news, things fit.  And its REALLY NICE not having that gosh darn, POS, good for nothing blow off valve there!



And of course, with all of my projects, there is another tragic twist.... :roll:

Looks like I have to take the cam out to change the valve lash shims.  There is a little ridge of aluminum right next to the cam towers that makes it impossible to get the shims out.  This ridge serves no purpose to either a mechanical head, or a hydraulic head.  I missed it when I compared the two heads side by side.  If I had noticed it, It would have been very easy to remove.  I had a full set of hydo lifters too, but I don't have a Hydro cam.

As far as pulling the cam, yah it sucks.  But it isn't insurmountable.  I need to do it this way to get the car home befor the salt flies.  I'll just pull the belt. Rotate the crank forward 90°. Spin the cam and measure all the cylinders and record the values.  Pull the cam, change the shims.  put the cam back in, spin it and measure again just to make sure.  Rotate the crank back 90°, do the timing belt thing.  Fire it up.  It just requred a couple more hours that I didn't have.  I also need to check the injector spray pattern.  I didn't get to that.  I have four new SMOG gtd nozzles standing by too.

I'll probably pull the head, dissasemble it, and dremel out those ridges this winter while the car is in winter storage.

[saurkraut]

UPDATE:

Everthing is done except the intake plumbing, checking/re-nozzleing the injectors and setting the pump timimg.

Its supposed to snow an unspecified quantity around here the next few days.  My concern is road salt.  The car is in the U.P of Michigan, and i have to get it back here to store it for the winter.

I'm planning on doing the injectors tomarrow mourning, fireing it up, and if its not salty, take it for a test run.  Then I'll pull the bumper, put on the draw bar, and drag it back here behind the TQW, if the roads haven't been salted.

There has been snow in the extended forecaste too.  So it may be right into the barn, and up on jack stands.

[arb]

Its supposed to snow an unspecified quantity around here the next few days.  My concern is road salt.  The car is in the U.P of Michigan, and i have to get it back here to store it for the winter.

Rent a U-Haul car trailer and use a couple of large tarps to cover your car, if you have a truck to pull it.

[saurkraut]

If they throw salt, thats probably what I'l have to do.

Keeping my fingers crossed for a snow/rain mix that doesn't accumulate....

[Smokey Eddy]

I had a three notch in there when my protrusion is the smallest possible.
My car was rendered useless when it got too hot or too cold for starting up again. And my economy when it was last running was 20mpg  :?

[SR Heer]

From what I know about HGs and VW diesel engines is that when it comes putting on a thicker than recommended HG -  it should not make any difference on how a normal - stock - healthy engine runs! In other words if putting a 3 notch or holer HG on when piston protrusion only calls out for a one notcher or holeror makes an engine harder to start or not run right when hot then some thing else is not up to par. Compression gages cost us $29 here at Harbor Freight in the US. I don't know what they would be in Canada but it behooves one to know what their engine's compression is in each cylinder! This helps establish a reference base for problem solving.

[monomer]

This needs investigation. I plan on slapping a fresh new 1.9 head on my mech 1.6TD shortblock.



Turbo pistons, stock rods. how close is the valve/piston clearance?

[SR Heer]

I do know that piston protrusion in relations to proper HG thickness has a lot to do with piston to valve clearance. I also know there is no difference in engine performance between using a two hole HG when factory specs actually call out for a one - in fact I know that VWs have come from the factory that way.

Now a three holer in lieu of a one holer plus going onto a non stock 1.6block with 1.9head ? that may apparently become a different story all together!

Has anyone ever first handedly found out that putting a there hole HG on a block that only requires a one holer along with using the stock head ever resulted in any malfunctioning of an otherwise beforehand perfectly good working engine?

Yes as bearings wear and things loosen up a bit I say it is wise to error on the side of using a thicker HG rather than sticking with the original Bentley manuel specs that are for new factory engines.

[saurkraut]

I do know that piston protrusion in relations to proper HG thickness has a lot to do with piston to valve clearance.

Interesting.  How do you know this.  Please share.

Has anyone ever first handedly found out that putting a there hole HG on a block that only requires a one holer along with using the stock head ever resulted in any malfunctioning of an otherwise beforehand perfectly good working engine?

Yes, as a matter of fact, the engine in this post was assemembled with a 3 notch when I first put it togather a few years ago with a 1.6 head.  This was a full rebuild, including an overbore to the first oversize.  I was in a hurry, and didn't bother making the measurement.

The engine has always had a less than perfect cold start.  Even with new injectors, cold start knob pulled, and ambient summer temperatures.  The pumping pressure on all cylinders is over 400 PSI.

Hot starts were just fine.  I'm sorry Smokey Eddy, you have something else going on there in your engine.

If I kept my foot out of it, and didn't run it full throttle through all the gears on acceleration, it got 40+ MPG.  Tragically, with my driving technique, it rarely achieved those results....

If you read my post above, I have also found some small areas of very slight heat damage at the edge of a couple pistons.

I attribute these two issues to running a three notch when measured piston protrusion called for of a one notch head gasket.

Here is a previose discussion of Squish and Quench: http://www.vwdiesel.net/forum/index.php?topic=8369.75

[SR Heer]

Thanks for the leads on 'squish' and 'quench' and I stand corrected on the idea of being able to use a 3 hole HG in the one hole prescribed application without any engine performance or cooling consequences! I agree then with Andrew that in doing so is bad advice and not to be recommended! If however the piston protrusion in a used engine measures out to be in the like say upper 10% of chart's limits I personally would think to use the next thicker sized HG would be a better 'safe than sorry' procedure.

But when it comes to being more 'safe than proper' ? - I don't know - has anyone out there tried using a one hole HG instead of using the recommended two or three hole HG and noticed if valves interfered with pistons or not? I haven't so then no I do not know for curtain that inversely using HGs improperly interferes with piston to valve clearance!

 
Now from the best that I can tell - my 98 Jetta did come with a two hole HG from factory when piston protrusion called out for a one hole HG but it was measuring in the upper part of limits for a one holer application. I was using a digital dial indicator to make measurements so they should have been accurate.  Has anyone had a similar experience? Thanks for all the good feedback! This is a great VW diesel forum!

Stephen

[saurkraut]

I don't remember if it was on this forum, or the old Diesel List, but there was some poster in Germany that had made a 1.6 bolck/1.9 head motor for rallying.

I think their piston protrusion called for 2 or 3 notches/holes.  Anyway, they successfully ran a 'one notch' thinner gasket with no detrimental effects.

I don't remember why they did it though.

The trick to keeping the valves out of the pistons is to have the cam bug nuts on in relation to the zero mark on the flywheel.  I like to stuff a couple of feeler gauges under the cam lock to get it level.  Then tighten the cam bolt with a sprocket holder, and everything is good.

[saurkraut]

I was looking for the post with the 'one notch thinner' engine and i found Jake's 1.5 SAE paper post:

Jake's 1.5 SAE paper

I didn't try to down load it, as my home internet access is via a phone modum.

Hey Libbybapa, I like your new avitar much better better :wink:

[SR Heer]

a 1.6 bolck/1.9 head motor for rallying.

I think their piston protrusion called for 2 or 3 notches/holes.  Anyway, they successfully ran a 'one notch' thinner gasket with no detrimental effects.

I don't remember why they did it though.

Well I would think that if going from a one hole to a thicker HG makes for a less than say perfect start in cold weather then it only stands to reason that going from a 2 or 3 hole HG to a thinner one with a 1.9 head would only help make cold weather startings more perfect in that by using the 1.9 head with its larger pre-chamber cavity which effectively lowers the CR then might not using a thiner HG actually help the squish and quench running properties of engine - maybe something to keep in mind?!?

[saurkraut]

Made it back home on Saturday all safe and sound.



Drove through 4 white outs and, fortunately, no salt on the roads.  The front of the car was caked in snow for a while, but it all melted off by the time i got home.

Only freaked my self out 5 times when checking my rearview and saw a car following way too close.  :shock:

Its in the garage, and we're supposed to get freezing rain today....  here comes the salt.

Just a little putz'en to do, and I'll fire it up.

[zukgod1]

this is awesome. It will be cool to see another one of these on the road