oil leak between head and block

[BlueDog]

I forget which head gasket to buy from Jack. He lists one notch, two notch and three notch. Do these three relate to the mechanical head engines only?

[82vdub]

You should be able to see a piece of your head gasket sticking out next to the front water outlet on the head. I believe it's to the passenger side. You should be able to count the notches in that gasket, or just get a 3 notch as it's the thickest one made. The pistons in these engines actually rise up out of the block a bit, and that's why the different thickness gaskets.

[BlueDog]

I wonder if the ones with the notches are for mechanical lifter engines only. Mine is hydraulic lifters and now I see that he has a separate price for head gaskets - hydraulic. I suppose that's the one I need. The head is off. The remaining portion of the broken bolt came out easily.

[82vdub]

hydraulic lifter engines have an extra oil drain hole that the mechanical lifter engines don't, so they physically use a different head gasket, but there's still one, two or three notch type.

[BlueDog]

Well, I wonder how much difference does it make to use a 3 hole HG instead of the 2 hole one.

[82vdub]

It may not make that much of a difference, until the temp gets low enough where higher compression will help ignite the fuel easier, or the engine gets worn and the compression gets low.

[BlueDog]

I guess those two reasons are enough, I'll send it back to Jack and ask him to send the one I ordered.

[BlueDog]

Installed the new head gasket. Got the right one, a two hole, from Jack. Started it today. Hard starting but finally did. Seems to run okay and the timing work went well. The problem though is that oil is being pushed from the crankcase up and out the dip stick hole. Didn't do that before. What could be causing this problem?

[82vdub]

You can search the posts for lots of conversation on this, but you've got a lot of blowby into the crankcase and that's pressurizing the block. The first solution is to "T" all the hoses together that go from the valvecover to the intake, with the port on the block. If you've got the diaphragm style vacuum pump, that will use the port on the block to put the air it pushes into the block. If you have the Vane style pump, the port on the block will typically just have a blank plate on it. Some have had blowby bad enough where "T"ing all the hoses wasn't enough, and they had to enlarge the hole in the intake manifold (if it's the style that goes into the intake) with a larger hole so it could move more air.

See these threads for a start, but there's lots of discussion on here about this.

viewtopic.php?f=8&t=7693

viewtopic.php?f=8&t=8828

[BlueDog]

But it didn't pump oil out the dipstick before I installed the new head gasket. And there's a lot coming up and out. When I had the previous HG in only just a tiny bit of oil was spurting from between the head and the block and that is why I changed the HG. Is it really that having a new HG is making blowby become apparent?

[Quantum-man]

The only test you can do is to put your old gasket back on!

[Fatmobile]

The only way I can think of that a head gasket would increase crankcase pressure is if the oil return holes got blocked,.. and I don't have any idea how that could happen.
If you can see these holes are open then it must be something else.
It is an NA MK2 then you can drill out the restrictors or see if removing the hose from the intake helps at all.

[Quantum-man]

As well as hydro/non, there seems to be a range of vent/oil drain sizes.in heads and gaskets if not blocks also.
If a slightly smaller one [gasket] was substituted, it may have the effect you have experienced, especially, I should imagine, on a 'well used' engine.

[BlueDog]

All fixed and running good. It turns out I did not have oil gushing out the top of the oil dipstick tube; it just looked like it. At the top of the oil filter mount I have a 1/8" inch nylon tube installed that runs to my mechanical oil pressure gauge at the dashboard. I must have damaged this tube when working on the HG change. From a tiny cut in this tube oil was spraying out to very near the top of the dipstick tube. This tricked me into thinking it was coming from the dipstick tube. It was a lot of oil. Way more by far than what was originally the little spurts from between the head and block. It wasn't until I got out of the driver seat, left the engine running, examined the oil leaking problem up close, that I learned what was really happening. I appreciate the help I get on this forum; especially 82vdub on this project. Thank you.

[bscutt]

Much better outcome than a repeat headgasket. I hate it when stupid little things like that run you around in circles. My 82 was making bad noises at high rpm ~3K) like a high pitch pinging noise and yesterday I traced it to the little fans on the alternator hitting the casting because the alt flexes a little in it's mounting at higher torque and rpm. Loosening the belt a small amount to make more clearance and shimming up the alt pivot bolt area some got rid of it. Glad it wasn't valves hitting pistons or something ugly like that