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Good morning all,

I need the correct weights for gearbox oil and diff oil (is that also the back axle oil?)

In particular I am looking for the spec of these oils, eg, 30w 20/50w, containing EP or not, or whatever. The problem is that products available in the States are not available here in Ireland.

Secondly, can anyone tell me how do air bubbles form in the fuel lines/filter? This happens whan the motor reaches around 160deg/cent on the dashbord dial, causing problems when trying to restart.

Slan go foill,

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Hopefully you meant 160 deg. fahrenheit, not centigrade! Two sources for the bubbles, one would be a leak on the suction side (before the pump) allowing air to enter the gas stream. It wouldn't necessarily be large enough to cause a gasoline leak when the car is static. The other possibility is the vaporization of the lowest-boiling fractions of the gasoline. It's not entirely uncommon when an engine is shut off as the temperature usually rises significantly at that point. Remember, lowering pressure decreases boiling points of liquids, so the gasoline on the suction side (before the pump) is most prone to boiling, that resident in the carburetor next, and that in the fuel line between the pump and carburetor the least likely (assuming a good needle and seat and pump valves). When the pump stops (engine stops), the pressure in the suction side returns to atmospheric pressure, i.e. the same boiling point as the fuel in the carburetor. Does your 34 have the factory heat shield around the carburetor?

For year-round use in most climates SAE 85-140 EP gear oil is appropriate for both the transmission and the differential. I've used that in my 34 Eight for 30 or more years, I'd be suprised if you can't find it in Ireland, it's pretty much of a universal product. Packard's recommendation were (probably, w/o looking it up) SAE 160 in the summer, 90 in the winter, EP (hypoid) of course for the differential, EP not needed but OK for the trans & steering gear box.

I'm surprised you have a vapor lock problem in Ireland's cool climate. Possibly with the wedding and limousine work you spend a lot of time idling or driving very slowly which can lead to excess heat under the hood.

The bubbles themselves are not a problem unless they cause vapor lock. If you see a few bubbles don't worry unless the y become bad enough to prevent the fuel pump from working and stall the engine. This is known as vapor lock.

With today's cheap gas the boiling and vapor lock is more common than it was when your car was new. Today's cars do not suffer this way because the fuel injection keeps the fuel under pressure.

If you have a problem with vapor lock there are 2 solutions.

One is to install a fuel filter with a small bypass and run a line back to the tank. This syphons off a small amount of gas along with the bubbles and passes them back to the tank.

Many Japanese cars of the 80s and 90s used these. The filter looks like a normal filter with an extra pipe coming off it. Any brand will do, look for one with the same size fuel lines as your car.

You will have to install a new return line to the tank or some people tap into the fuel line before the fuel pump.

The other solution is to add an electric fuel pump back by the tank. This can be used for priming the carb as well as providing extra fuel pressure. It should be wired to a manual switch for the driver to control it.And should be wired to keyed power so it automatically shuts off when you turn off the key.

Thank you for your replies.

Does the fuel line exit from the top of the fuel tank?

Is there access to it apart from removing the tank, eg through the trunk bottom?

Ps; it has been quiet warm here the last few weeks, roll on global warming!

Pat.

No access to the top of the tank other than by dropping it. I forget whether the fuel pickup in 34 was at the bottom, or a drop tube from the top with the sender, but I seem to remember it's at the bottom. If you need, I can go out and take a look.

If your tank (we're speaking of a 34 here, right?) has to come down and it still has the soldered brass expansion bellows on the filler neck, it can be a bit of a close thing as of course the filler neck is in the tail light housing and a very snug fit! If so, the tail light has to come off, along with the inner fender splasher. Perhaps your metal bellows has been replaced with a piece of large diameter gas hose as many have been, makes it easier.

Removing several of the bolts that hold the filler flange to the driver-side of the tank side can also be challenging with the spring right up snug, but be patient.

Because these engines have the fuel pump on the non-manifold side of the engine, they are particularly resistant to vapor lock even with today's swill for gasoline.

Would you mind having a look to see where the fuel outlet is located?

Yes, its a 34' 1101 Club Sedan.

Thanks,

Pat.

Dave,
I've recently dropped my tank to sort out why the gauge was'nt working and the exit pipe is drop down from the sender unit. As an added note the tank was'nt too difficult to remove and as you state the filler connection is a bit tricky but I managed to undo all the small bolts without having to remove the light and splasher.
Terry

Hi Pat,
Iv'e also been looking for some sae 160 oil but I was told by a supplier of classic oils in the U.K. that this is no longer available only 140 or 250
Have you tried CLASSIC OILS AYLESBURY HP21 7EB TEL.01296-381294
Best of the Irish luck
TERRY

Good morning,

Thank you all for your various suggestions.

There is no heat shield btween carb and engine but I will look into it.

Someone suggested fitting a one way valve into the fuel line to stop the petrol being forced back into the tank due to air bubble expansion.

If there is a solid fuel line going into the fuel tank, how is it removed prior to tank removal?

Pat.

Solid steel 5/16 fuel line is still sort of flexible, mainly due to all the bends that are required to clear the rear axle. Undo the last support before the tank and undo the tank connection, you'll be able to pull the steel line out of the tank without removing the tank. Some gas will come out, it would be best to drain the tank prior, but not absolutely necessary.

Cut with a tubing cutter, there are small ones that don't require much clearance. Measure the check valve and allow yourself enough space for two connections on either side. You'll need to cut twice, measure carefully. Before flaring put the new connectors on either side (I've forgotten this step, and boy do you feel stupid) and thread everything together.

My check valve came in a bypass kit for my electric fuel pump from Then and Now.

http://www.then-now.com