Gaz 67b - 1943 -Uses Ford Model B engine made in USSR - South West Wartime Vehicles

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South West Wartime Vehicles

A page for those with vehicles that might have been seen in the 1940s. It is always hard getting these vehicles together to add to re-enactor displays. A lot of vehicle owners seem content lining up at the same old rallies.

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Created: Jun 16 '15
Admin: webmaste

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webmaste Jul 12 '15

On return from Victory in Europe weekend the engine started missing and getting hot. Here's what I have found by taking off the cylinder head.

I have the head off now and can see what has happened there. Water leaking into #2 when stationary filling cylinder and intake and blowing into water when running. #3 compression leaking into water system only I think.

Overnight the oil level rose and there was a couple of pints of water in the oil when drained. The cylinder head has 2 cracks and they have been there since we had the Gaz, but this time I think we'll have to get a new one or can cracks be repaired.
We have been losing water since 5 years ago and I sort of hoped it would go away after the re-build (wishful thinking!). When putting the head on last time a stud sheared, I took head off again, put in new stud and re-tightened. None of that would have helped! I guess/hope that water could leak into oil via pistons and valve guides?

Attachments:

head crack 2.JPG (30Kb)
head crack.JPG (17Kb)

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webmaste Jul 14 '15

1. The Ford Model A head and water pump have arrived and I have had a look at it in situ. The A head will fit, but there are issues as follows:

a. Two "steam holes" need to be blocked to use the A head.

b. The water pump would have air above it due to the radiator being so low.

c. The radiator and grille need to come off to fit the water pump because the A pump goes deeper into the head, so needs more depth to manoeuvre when fitting.

2. We are trying to source another B head in the USA - Bert's Model A Center, whilst West Cornwall Engine Services looks at the original head. It's possible that Trapper Industries have a head, they are checking its condition tomorrow.

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webmaste Feb 2 '17

GAZ 67B Engine re-build

It is almost 2 years since the engine re-build, so we thought it would be nice to fit an oil pressure gauge for the first time in the life of the Gaz! The Model B engine doesn't have a lot of oil pressure so a 0-10 psi gauge is required. These are hard to find with Rex-A-Co being the only ones who appear to do it (see image). On start-up, the pressure slowly rises to about 8 psi. As the oil warms it reduces to about 2 psi on idle. We haven't been working with it yet as an over-charging issue needs to be sorted - regulator in the post! Another blog to follow on that one!!

The Forum post is edited by webmaste Feb 27 '17

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1stPanzer Feb 2 '17

Blooming' eck! What was it my Aunty used to say? "A bit of tin and a bit of board, put them together and you've got a ...!" At least it is keeping you busy :-D

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webmaste Feb 27 '17

Over 2 years ago, the Gaz 67b was

back on the road and is still being run in.

WATER TEMPERATURE

The engine has had a new oil pressure gauge and now a water temperature gauge, to better monitor what is going on. As I understand it, the Model B engines never had a water temp thermostat. What do you think about fitting one? There are 2 choices 160 Deg F or 180. Picture right.

A recommendation from a chap on Facebook - "As a long time model a and b engine builder ,, I never do under stand why you would want to risk a block crack in an engine that was never designed to run thermostat ?? I would advise against this unless you do want to possible crack the block on one or the other or both interior exhaust ports. I have seen this many times ... and many times it can be tracked to using a thermostat. If you MUST use one, please enlarge the small bypass hole in the unit to allow those hot areas to cool ,,,,"

OVERCHARGING ISSUE

In the process of fitting instrumentation I discovered that the generator was over-charging and probably has been for 7 years! The indicator went red at 15.2 volts on quite low revs. A quick check revealed a faulty regulator. I found a similar looking regulator in the Lucas RB 340 - see photo. An additional i strument is now a voltmeter. The 3 instruments are tucked out of site left of the drivers knee. Photo to follow.

The Forum post is edited by webmaste Mar 11 '17

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webmaste Mar 2 '17

Here