WC62, 63 OWNERS POWER QUESTIONS

[gfbeef]

I have a 1943 WC62 which I finished the restoration on in 2012. The engine has 100+ psi on all cylinders with new rings and ground seats and new valves. I have gone thru 3 Carter carbs and the performance is almost always the same; max speed downhill about 35 with 30 being a constant. I finally found a Zenith 29 left over from the Scout Car restoration. I rebuilt it and have some improvement in operation. The question is; is this performance expected from other WC62/63 out in the world? I am planning on taking this 6x6 on the Route 66 convoy but would like to have some margin of performance better than what I have now.

I have seen at least one posting where the Offenhauser 2 carb set up was used on the 230 engine but can't seem to find it now. Does it help on the power performance and speed??? I would hate to spend $2K on the modification and it not help.

History and suggestions please., Best Regards, Mike

[Marty, SoCal]

I could not get the governor to work properly in my friend's professionally rebuilt 3/4T WC Carter carb, it wouldn't allow speeds over 30-35, just like yours. It also had a bad stumble I
believe due to an inop vacuum actuated accelerator pump which made shifting the crash box a PITA. Nothing I can see is worn or binding in it, it all looks new, it just does not work properly.

Anyways, I had a NOS 50's Dodge BBD two barrel with a manual choke, so I made an adapter plate on my milling machine and some bolt on linkages to make it work on his engine. It will now run at 62 mph all day long. (It has 4.89 gears).

Instead of the dual carb intake, there is a two barrel Weber carb conversion kit available from Vintage Power Wagons, (and maybe others) which has the adapter plate to the stock intake, should accomplish the same thing. Also, simply installing a stock BB one barrel from a civilian Dodge would bypass the internal governor and should give you the speed it's capable of. Not much hood clearance on a 3/4T or 1-1/2T so a short aftermarket air cleaner is needed.

I also installed a vacuum advance distributor in it which perked up the part throttle performance while the original 1950's diaphragm lasted. When I get caught up on other projects I will probably adapt a 70's electronic slant six distributor to work on his truck, since it's already 12 volts an parts are readily available for it.

Everything I did and will do can be reverted to stock in an hour or two.

Hope this helps!

[Tankdriver]

I can not see the 1,000's of WC built running this set up only running 35 since they were governed at 54. So the set up must have worked correctly when built, or the military would not have accepted them. My engine badly needs to be overhauled, and it easily runs 45 and above. Just takes a while to get there.

A couple things to check....

Since you have rebuilt, swapped carbs, that should be OK. What fuel pressure and flow are you getting? What fuel filter are you using? Are your fuel lines leaking, and sucking air. Do you know how to properly adjust the governor. Be sure and check all vacuum lines. If you have vacuum wipers, are they leaking? If you have rebuilt the engine, is the cam correctly times? Is the timing correctly set. What is the gap set on the points, incorrectly gapped points will change the timing.

I know you probably know these things, but something has been over looked. You should not have to change a design that is over 70 years old to run correctly.

[gfbeef]

Well, everything in the stock fuel system has been replaced; ie, lines, filter, tank POR"d and I have installed an electronic fuel pump for back-up. I have decided to install a Pentronic electronic 2 spark module in the distributor but had not thought about a vacuum advance; that does make sense. I will call Yens @ VPW and pick his brain about the 2 barrel setup bypassing the governor. At least I haven't spend more money for nothing as I would with the 2 carb setup. The governor is supposed to kick in at about 3600 rpm but I can't get there with the present Zenith.

[Marty, SoCal]

As I said, my friend has a couple of the governed Carters, and I couldn't get the governors to allow speed over 35 with any of them, either. I'm pretty good with carbs, being a smog mechanic that worked at a Jeep dealer for 18 years when a lot of jeeps still had carbs. All the settings were done by the book, one carb was rebuilt by Midwest Military. Also, I could not get the vacuum actuated accelerator pump to work properly in any of them. I'm assuming there must be some point of wear or the modern kit replacement springs are not the proper tension to make it work correctly. When I installed the BBD, I didn't change the fuel pump, lines or anything else. I had previously installed an "EFI" type filter which seems to do a good job of keeping the dirt out of the carb (The emulsion jet was getting plugged regularly in the original cab before I installed it, even after the tank had been cleaned out and all new steel and rubber hoses were installed.)

My friend and I will be at the Pleasanton convention with his Command Car and will have in the display only area, if anyone want's to check out the carb installation.

[Tankdriver]

Something is still is being missed and is incorrect, as there were thousands of these running correctly. So the basic design has to have preformed correctly. If not they would have stopped production and used a 2 barrel in them. It does not have a vacuum advance; it has a centrifugal advance. Do you have a vacuum gauge? They can tell you a bunch of what is wrong, cheaply......



You can also check the fuel pressure at the same time.

The vacuum piston is adjustable for the amount of stroke it uses when it is released. It has 3 settings, but that should not affect the top speed as it acts like a acc pump.

Manual information

Engine Does Not Develop Full Power.

(1)
IMPROPER FUEL MIXTURE. Inspect air cleaner for restriction of air due to accumulation of dirt in oil reservoir (par. 69). Clean fuel filter (par. 74).

(2)
Low FUEL PUMP PRESSURE. See paragraph 34 a (3).

(3)
INTAKE MANIFOLD OVERHEATED. Check setting of heat control valve (par. 56).

(4)
IGNITION TIMING LATE. Check with timing light and adjust (par. 99).

(5)
RESTRICTED EXHAUST. Inspect tail pipe for damage; muffler for clogging and repair or replace (pars. 77, 78, and 79).

(6)
COMPRESSION Low. Test (par. 55). If low, notify higher authority.

(7)
VALVES STICKING; VALVE SPRINGS BROKEN. If causes listed in steps (1) through (5) above are not evident, notify higher authority.

[Gordon_M]

My experience with 3/4 tons is that they will run right up to the 55mph where the governor cuts in, so that's what you should be looking for. Given all the extra weight that the 6x6 is hauling it would certainly get there more slowly, but it should still get there.

Only two key areas would be engine condition / performance and drag in the drivetrain or hubs. My starting suggestion would be to drive it to some road with a very slight downhill slope, what physicists would call a 'friction compensating slope' While everything is still warm from getting there, switch the engine off, put it in neutral, handbrake off, and see if it will roll away easily downhill and gather speed. If it does your drivetrain and hubs aren't the issue, it's the engine. If it won't roll away easily = hubs and/or drivetrain.

Could be a combination of both, of course, but that would be a cheap first check.

[Ernie Baals]

Something else to check
Are you sure your speedometer is reading correctly?

[Marty, SoCal]

What is the cure for a governor that will not adjust to give speeds over 30-35? On my buddy's Carters, any adjustment I tried would not allow any higher speeds. A simple non-governed carb swap and it ran perfectly.

[Gordon_M]

What is the cure for a governor that will not adjust to give speeds over 30-35? On my buddy's Carters, any adjustment I tried would not allow any higher speeds. A simple non-governed carb swap and it ran perfectly.

They are a very simple velocity governor. Adjusting the spring pressure - or back-pressure I suppose it is technically, should allow the engine to run flat out. Butterfly and shaft in upside down? incorrectly assembled? I think running it without the air cleaner may affect it too.

[halifaxgroup]

I can get mine up to 45mph but it takes a while. The comment about the speedo being correct should be taken seriously if it has ever been replaced. A large number of these reproduction speedos were sold and they seriously under indicate the true speed. Paul

[Marty, SoCal]

It had the stock oil bath on it while trying to adjust it to run to spec. Yes, a properly functioning Carter governed carb on an otherwise properly tuned stock 230 should run to the rated speed at sea level.

The same carbs that would not allow the governed speed to exceed 30-35 also didn't have any accelerator pump function, so considering the expense that my friend had already went through trying to get a couple stock carbs to run properly when all he wanted to do was drive his truck, I put on the different carb and afterwards, experimented with the vacuum advance distributor, since I had one handy. (ETW1 carb kits are $60, reman exchange carbs are over $250 once shipping is figured in at Midwest Military. Even core carbs go for well over $100 on epay )

The NOS BBD I had in my stash was given to me free a few years previously by a neighbor, the adapter plate took me a few hours to make on my mill with a piece of scrap 1" aluminum plate, the linkage took another couple hours to make, because I wanted it to be bolt on without modifying the truck permanently and the stock hand throttle needed to work. I still need to make a more old school looking air cleaner for it. We recently took the Command Car up to the local mountains (Big Bear) at almost 7000 feet in the high 80's temperature with no vapor locking, the truck ran great. We are not looking back!

Here's a video we took soon after I installed the carb and 4.89 gears, we were driving on the freeway to a rifle range in Azuza Canyon, about a 45 mile trip each way. Click on the pic to start the video:

[Gordon_M]

Well whatever works, but a word of caution. If you are running without a governor do not over-rev the engine. The primary weak point is the head gasket, so that will normally go first between the two close pairs of cylinders, but if you don't over-rev it you won't have to find out ...

[dpcd67]

I have owned 4 M37s; they all would run at 55 with no problems, and my 63, will easily run at 60+ with 4.89s. I have found that when your carb stumbles and won't gain power, it is usually the accelerator pump, but replacing just the piston won't help. Usually it is the bore that is worn or pitted, and the carb body needs replaced. Since it runs with a BBD, you know it is the ETW1 that is the problem. I am currently restoring a WC63, also with an ETW1 but am nowhere near re-assembling it yet.

[Marty, SoCal]

If we can find a Zenith, we may try it, since I believe the 1942 3/4T should have one of those, anyways. His truck went through at least one European rebuild.