Our LRDG Chev

[Andrew H.]

A quick update:

(i) Yesterday we used the electric drill in the distributor hole as suggested and got the oil to come out of the rocker holes, but only just - it just seeped out of a few holes but didn't spurt out. Is that what should happen? We don't want to run the engine for more than a few seconds until we are sure about this.

(ii) Can anyone post a pic showing how the throttle linkages go together on our kind of RHD Chev? All the Google pics show only LHD linkages, which are completely different. One of the linkages crosses from the accelerator pedal behind the engine to link up with the carby, but we cannot see where it fits or what it should be attached to (maybe the firewall?) We didn't take enough photos and now cannot remember.

[Lynn Eades]

Andrew the oil supplied to the rocker gear is at reduced pressure, if I recall, regulated by a cut out or cut outs in a cam bearing surface. As long as you are getting some to each rocker it will be fine. It runs down the rockers and lubes the valve stems and the push rods and cam followers also.
When you have it running you can check it with the cover off.
It is probably a good idea to run along the rockers with the oil can before starting if they look a bit dry. some rockers will move sideways to get a bit of oil into the bearing surface (hopefully they were lubed on assembly)

[Andrew H.]

Thanks Lyn,
Thats reassuring to know. We don't know what psi we were getting up to with the drill, as the pressure guage is not working properly.

[motto (RIP)]

Andrew, the FLOW to the rockers is controlled by a restrictor which doubles as a connector nipple where the oil comes out of the side of the crank case. The rockers don't need much lubrication, they certainly don't need pressure, just the presence of oil is enough.
Engine oil PRESSURE is pretty much controlled by the distributor valve which creates a back pressure in the same manner as a relief valve.Of course engine wear also plays a part when the engine has been in service.
Oil tapped off from upstream of the distributor valve feeds the main bearings, camshaft bearings, timing gears and rockers.
Oil that passes through the valve supplies the sump manifold for lubrication of the big ends.
It sounds complicated but it isn't really.

David

[Andrew H.]

Thanks David, we will have another look at it tomorrow.

[Andrew H.]

Recently we have been working on the drive-shaft and universal joints. The original drive-shafts could not be used so we had to source some from a cannibalised hulk that we have access to. Yesterday we did a bit more work on the motor, tweaking the timing, carburetor and fuel pump and running it very briefly (still no radiator) to check that everything is working properly. Un-muffled, she makes a throaty roar at full tit!

We were very pleased to see that the drive-shafts are aligned properly and rotate smoothly and without any vibration. When we pressurised the brake-lines for the first time, we found several leaks at the junctions. Tightening them up did not fix the leaks. We think this might be because we only single-flared the pipe, as we don't have a double-flaring tool. Would anyone like to comment on single versus double-flaring the brake line pipe?

[Grant Bowker]

MB-F1 and MB-C2 both specify double flares for CMP trucks. So does the Ford shop manual for Conventional and Modified Conventional vehicles. I don't have access to the corresponding Chevrolet manual. With the use of double flares being so widely specified (up to current vehicles), I would assume your truck probably used them too. If this is correct, then the fittings and junction blocks would all be designed to match the thickness and profile of double flares and might very easily not seal properly on a single flare. My understanding is that double flaring also reduces the chances of the line cracking from the free end. Since single flares are cheaper to make, I think the manufacturers must see a benefit in using double flares that outweighs the added cost.

There are a variety of double flaring tools that vary widely in price and ease of making acceptable double flares. Nickel-copper and steel lines are generally easier to form than stainless steel. Among the cheapest I found on ebay was http://www.ebay.com/itm/Tubing-Doubl...610665&vxp=mtr
I did all-new lines for a C15A in stainless using this http://www.eastwood.com/professional...ring-tool.html without any spoiled flares. I had done some stainless flaring with a tool like the cheaper variant with mixed results and decided I would go with the Eastwood tool when doing the complete truck. I found it much less frustrating to use than the simple traditional (cheap) machine. One limitation is that it can only flare up to about 1-1/2" from an existing curve in the line. It may work better to plan your lines to flare and then bend if possible although this gets harder to do if the same applies at both ends of the line.

[motto (RIP)]

All components of conventional automotive braking systems to my knowledge are manufactured for use with double flared connections. There is no way that I would attempt to use single flare connections unless in an emergency in a remote area. I highly recommend that you procure double flared lines one way or another.
A few years ago I finally got around to replacing my old double flaring kit with which I probably achieved a 50% success rate with a modern Eastwood kit purchased online. It wasn't cheap but turns out an excellent job almost every time and I'm very glad I invested in it.

David