'67 engine build

[veedubcrazy]

Doesn't #2 and 4 share the same cam lobes? Maybe cam going flat?
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1967 Deluxe Sedan

[johnnypan]

With a cold running engine spray a flammable substance around all the intake manifold connections,if the engine picks up speed or starts running smoothly that is where your vacuum leak is....starting fluid works best,but is dangerous...

It appears you have carb issues as well,check the float for buoyancy and lower your float height.


hang that disco smoke machine on the shop wall,it will make a great conversation piece..

[maboyce]

Well, I'm surprised. I tried a number of things, including running without the muffler (loud and exciting) and cleaning the anti-seize lubricant off of the spark plugs in case they weren't grounding properly, which the Internet says can happen. Then I went ahead and shot water (since I have nothing else that won't damage paint or make a mess) at various joints with a spray bottle. Sure enough, spraying water under the intake manifold flange on the left side nearly kills the engine. The dark fuel residue on the outside was significant.

The leak survived two changes of heads, a new manifold, and several reassemblies. Because of that I'm not really sure how I'm going to fix it...both manifolds I've used are 'tight' and seem to be a little narrow for where the heads are, so maybe I need to bend the elbows out a little. I had been relying on the nuts to draw the flanges into place.

[johnnypan]

[maboyce]

I took the engine back down to the short block and reassembled it fully. During the process I went ahead and re-painted the cylinder tins and touched up the top of the fan shroud where the air cleaner had been hitting it.

I also touched up the manifold, because I had tried to bend it outwards a little so it would seat better.

I took the opportunity to do some more modification of the oil cooler. The metal bands on the sides that held the foam sealing strip had been fouling one of the spark plug wire clips and the throttle cable tube, and with repeated removal and installation of the fan shroud the wire clip had finally broken inside. I was also nervous about the foam strip and bands decreasing the airflow to that side of the engine.

I'm a little curious what engine this oil cooler was originally for. It's not a doghouse type for late Beetles, because it has a flat bottom.

The side bands are brazed to the body of the cooler, so I got out the cutting wheel and CAREFULLY ground through the steel of the band until I saw the yellow of the brazing underneath. Cutting into the oil cooler body or weakening it in any way would be very bad...I erred on the side of caution by leaving nubs of brazing in place rather than try to smooth the surface.

I think that, despite the modifications, it's worth it to use this older and unused genuine part rather than go with a cheap recent part or a used and 'cleaned' one. I had a cleaned and tested one that I threw away because old oil came out of it.

Here are the grinds:

I shot paint at the corners to finish the job.

Back to reassembly. I put the exhaust system back together with new gaskets and high-temp RTV.

I went ahead and cleaned all the soot off of the spark plugs with mineral spirits and a brass brush.

The rest of the reassembly was as previously described. I did go ahead and fill some divots in the intake port surfaces with tiny amounts of Dirko before I put new sealing rings in place. I installed the sealing rings with the seam up this time, if it makes a difference.

With everything back together, I ran the engine again...no change. A little better than the previous run, maybe. I checked the manifold joints with water, and didn't find the leak this time. I think it must have been an artefact of my re-using the sealing rings that time, and not the underlying problem.

[maboyce]

...which was probably this.

At the end of the most recent test run, I noticed a little bit of fuel dampness around the throttle shaft on the carburettor. It made me want to check the fuel pressure again, just to be sure.

I hooked up the pressure gauge as I had done before, and there it was, to my amazement and relief. 4 psi (28 kPa) where there should be 2.8 (19 kPa). I realise what happened now - lapping the bottom of the pump when I installed the new diaphragms changed the effective pump stroke! Now I need to make some more gaskets to raise the pump and see if that makes a difference.

[maboyce]

Hmm. I made some gaskets and put them under the pump. I found two was enough to bring the fuel pressure down to 2.8 psi on the gauge. While it eliminated some popping at speed and when closing the throttle, the idle is still not right.

I continued to add gaskets, only to find that the fuel pressure never went down much further. At five the pressure was still 2.4 psi.

A new symptom is a stumble when closing the throttle - it continues even with the new fuel pump gaskets. The Bentley manual says that is a symptom of an idle that is too rich - but I can't set the mixture screw any leaner and keep the engine going. I wonder if the prolonged high fuel pressure has done something to the float or needle valve in the carburettor?

[veedubcrazy]

I think your on the right path here.
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1967 Deluxe Sedan

[maboyce]

Yesterday I went ahead and took the top off of the carburettor to make sure everything was OK. The float was floating, and the needle valve moved freely, so that was that. I had a different needle valve in a leftover carburettor kit, so I put it in just for kicks. It was identical to the other one.

Since I'm to the point of checking unlikely things, I decided to check valve timing and duration.

I taped my degree wheel back on the pulley and lined up the 10 degree notch and mark. In the 'Engine Technical Data' section of the FSM, where the valve timing information is, it says that the timing is to be measured with 1 mm of valve clearance. I adjusted cylinder 1 accordingly, and then turned the engine over slowly. I kept my hand on the rocker arm and moved it back and forth in order to feel when the clearance was being taken up. Just at the point when I couldn't move the rocker any more, I read the mark at the top of the degree wheel.

To keep from getting confused, I did one cylinder at a time, setting the valves back to 0.15 mm clearance when I finished. For cylinders 2 and 4, I also had to remember that 'Top Dead Centre' on the degree wheel was actually bottom dead centre.

The specifications:

Intake opens before TDC: 7.5 degrees
Intake closes after BDC: 37 degrees
Exhaust opens before BDC: 44.5 degrees
Exhaust closes after TDC: 4 degrees

I read:

#1
Intake open: 2 degrees
Intake close: 38 degrees
Exhaust open: 39 degrees
Exhaust close: 4 degrees

#2
Intake open: 3 degrees
Intake close: 37 degrees
Exhaust open: 39 degrees
Exhaust close: 3 degrees

#3
Intake open: 4 degrees
Intake close: 37 degrees
Exhaust open: 42 degrees
Exhaust close: 2 degrees

#4
Intake open: 4 degrees
Intake close: 37 degrees
Exhaust open: 41 degrees
Exhaust close: 4 degrees

I think these numbers are within my limits of accuracy for this measurement. It looks like I'm better able to detect when the valve closes than when it opens. I'm really looking for #4 to be different from the others, and it isn't.

On to lift. I used a 10 mm dial indicator on a magnetic stand stuck to the heater boxes. It would have been steadier to clamp the stand to the centre of the rocker arm, but I didn't have the hardware to do it. After some fiddling I could find a place where the magnetic stand would sit stably.

I made sure the indicator was parallel to the axis of the valve, which isn't quite perpendicular to the plane of the valve cover. With the valve closed, I pushed the indicator stem in until the revolution counter read '0' a second time (meaning 10 mm in this case). Then I turned the bezel to zero the hundredths scale.

I then turned the engine over by hand while watching the pointer. I took a reading when it stopped moving, showing that the valve was at the end of its travel.

#1
Exhaust 8.18 mm (0.322")
Intake 8.71 mm (0.343")

#2
Exhaust 8.35 mm (0.329")
Intake 8.71 mm (0.343")

#3
Exhaust 8.10 mm (0.319")
Intake 8.71 mm (0.343")

#4
Exhaust 8.11 mm (0.319")
Intake 8.65 mm (0.341")

Because #2 exhaust was the most different from the others, I repeated the measurement and got 8.28 mm.

Again, cylinder #4 is not noticeably different from the others, which is what I wanted to know.

[maboyce]

I made two discoveries while taking things off the engine yet again, to fix a popped-out pushrod tube seal.

The first was fuel residue on the left intake manifold flange, just like the last time. The seal ring underneath was quite wet. It was well crushed on the inboard side, but almost not at all on the outboard side. I can see score marks that would seem to indicate it was contacted by the flange, but only just. I wonder if a leak here would affect running, even if it was small enough not to be detected by the water spray?

The second discovery was more confusing - a large drop of water inside the #2 exhaust port. I can't tell if it dripped down from the heat riser tube, which I know gets condensation inside, or if it is water I sprayed on the outside somewhere. The former seems most likely - how would it get in against the positive pressure of the exhaust while the engine was running? During the low pressure period between exhaust pulses? It's still a lot of water.

And that's not the side of the engine with the weak cylinder...

[KTPhil]

[maboyce]

[58deadhead]

[maboyce]

This morning I decided to change the pushrod tube seals while I had the heads off, since they've been reused several times by now. I wiped the Hylomar clean as previously described on the heads and case, but decided to reapply it to the tubes themselves.

I put the heads back on and moved on to the leak from under the flywheel. I'm still waiting for new seals and gaskets, so I can't do any more test running for now.

I found a dry flywheel seal...

...and a damp case seam under the cam plug. Poop.

[Boom]

Should be an easy fix. Can you simply pop it out and install a new one.
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Ovals are Overrated.....Click to view image

67 Chubby White Chic

Düg Büg

dLk

[maboyce]

[maboyce]

I split the case this morning. First I took the heads back off and removed the pistons and cylinders. It was mostly the reverse of removal - I slid the cylinder off the piston far enough to expose the piston pin, removed the clips, used the propane torch to heat the piston (just as I did for installation), and pushed the pin out far enough to release the connecting rod. I had to turn the engine over to reposition each piston so that there was clearance to push out the pin.

I accidentally pulled cylinder #4 all the way off. It let me see the rings, which looked OK, though the first and second ring gaps were now closer than I want. I'm not sure if I need to re-hone the cylinder or if the parts are still new enough to just go back together.

I took off the sump plate and oil pump. The oil pump looked fine, with wiping marks but no new scoring.

Then I could remove the hardware and split the case. Everything still looked pretty good inside. All the lifters have circular marks on them showing that they are rotating as they should.

[KTPhil]

[veedubcrazy]

[johnnypan]

You tore it all down again? really?...this time ditch the nuts and bolts and use Velcro..

Hone the cylinders and reuse the rings...just run the hone through one or two passes as a glaze break.

Brake cleaner and scotch brite extra fine on the piston skirts.

Reuse the main bearings,but don't reuse the rod bearings..

Don't use any gasket sealer on the oil pump plate gasket,it reduces the efficiency of the pump.

case sealer like kuril isn't as effective as permatex ultra grey on the cam plug...the plug seal area is as precise as the case flange..