willysmjeeps.com

wesk wrote:Keep in mind that the spring you choose will determine the centrifugal advance curve that you will end up with. The tension is very critical to getting the proper advance curve. Size and shape is secondary to the measured tension the spring develops when selecting replacement springs.

Surplus City lists the late set but show POR:
http://www.surplusjeep.com/M38A1/m38a1- ... trical.htm

Have sent them an email inquiry, gave them my dist info. Will let you know what I hear back. Thanks for the link!

Spoke w/ S.C. today. "Out of stock" on springs, bushings, washers and o-rings. But I can send them my dist and they will rebuild it for $295.

I dont get it, Jack.. If they're out of springs, bushings and such
how the heck will they rebuild it

RICKG wrote:I dont get it, Jack.. If they're out of springs, bushings and such
how the heck will they rebuild it

I asked the same question Rick. Turns out they have some parts in the inventory to use for rebuilds, bushings they make as necessary, but none for sale.

I talked to an engine builder who said I might be able to find some springs that match. For example, buy a kit like this and compare the good spring I have to those in the kit:

http://www.summitracing.com/parts/MRG-928G/?rtype=10

I'm also going to check the local parts houses to see if they have any springs I can match up.

Well, after two weeks of being distracted by other things, I decided it was time to get the A1 running again. I took it to a local mechanic who works mostly on small engines but knows his way around all kinds of engines. I explained the advance spring issue. He pulled the dist and found that there were no advance springs, none, which means it had been running on the one that broke for a long time. He also saw that the holes on the advance plate were enlarged and the inside of the dist was full of ground up metal. He repaired the holes, cleaned out the dist body, put in a new set of points I provided and replaced the advance springs with brand new springs from a Briggs and Stratton lawn mower engine tune up kit. Yup. Lawn mower.

It's starting, idling and running better than it has for the three years I've owned it!

I gave him the curve info that Wes listed, but, because my crank pulley does not have a timing mark, he could not give me all of the advance info at various rpm. But he could tell me that full advance is now at 12 degrees with the Briggs and Stratton springs, which is real close to the 11 degrees that Wes listed for curve 1026.

The bushings were tight so no need to replace them.

So, need to rebuild your dist? Head on down to your local lawn mower repair center and ask for some springs. I found out that many times they aren't needed and get thrown away.

I took a second set for my parts box.

I'll post a follow up in a few weeks and let you know how this fix is holding up.

Jack

The RPM's listed in those distributor advance curves is for distributor RPM not engine crankshaft RPM.

It is much easier to accurately time your jeep with a mark on the pulley and a pointer on the timing gear cover. You can buy the pointer from John at Midwest.

We use a wiggler or dial indicator to accurately locate the piston on #1 at TDC. Then make the mark on the pulley to match the pointer's TDC or "0" mark. Then use a protractor or degree wheel to locate the 5 degree earlier mark for your advanced spark position.

wesk wrote:The RPM's listed in those distributor advance curves is for distributor RPM not engine crankshaft RPM.

It is much easier to accurately time your jeep with a mark on the pulley and a pointer on the timing gear cover. You can buy the pointer from John at Midwest.

We use a wiggler or dial indicator to accurately locate the piston on #1 at TDC. Then make the mark on the pulley to match the pointer's TDC or "0" mark. Then use a protractor or degree wheel to locate the 5 degree earlier mark for your advanced spark position.

Thanks Wes, I've got the pointer, just need to put the mark on the pulley. Copied your instructions.

Jack

So what's next Jack? Gonna hang a mower deck under the A-1??

RICKG wrote:So what's next Jack? Gonna hang a mower deck under the A-1??

Well, no, but I did go up to the local fab shop yesterday to see if we could put a rope starter on it!

Got it installed this morning, went together nicely, works great.



Jack

Jack, just saw a truckload of guys in white coats,
all carrying butterfly nets pulling into Ashton-better
lay low a couple of days!!

RICKG wrote:Jack, just saw a truckload of guys in white coats,
all carrying butterfly nets pulling into Ashton-better
lay low a couple of days!!

"They're coming to take me away ha ha, hee hee, ho ho,
to the happy farm . . ."

(they'll never catch me )

Jack

First, a good Independence Day to all! The little town (pop. less than 1,000) where we're staying does a great job of celebrating this day: pancake breakfast, parade on Main Street, town fair in the Park, cookouts and fireworks. Hope you have a good day too.

Well, the Jeep ran great with the lawn mower parts in it for about a day. But then both springs broke. I guess they were just too fragile to take the movement required. Oh well . . . at least I got a rope starter out of the deal!

So, I bought one of those replacement spring kits ($9 from local parts house) for a small block Chevy. The kit has three different sets of springs, light, medium and heavy. I pulled the dist yesterday and put the heavy ones in. Jeep starts nicely and runs okay, but doesn't have the crisp throttle response of the lawn mower springs. Talked to a local hot rod guy last night who told me that if I advance the dist a bit I'll get a more crisp throttle response.

Jack

Why not correct the spring issue instead of applying one band aid after another. Advancing the distributor will increase performance a wee bit but it will also cause a heavier load on your starter. The initial timing setting on these distributors is not meant to be the perfect performance setting. It is a compromise that takes into consideration the harder cranking by the starter if advance to far, the pinging or overheating of the coolant. The 5 degree BTDC mark is for the old regular gas we used in the 50's. If you have machined the head in the past and are running 87 or higher octane gas you can bump the advance to 7 or 8 BTDC.

My advice is to either find a pair of the correct springs or try the lighter Chevy set you have which if the not so crisp throttle response is being caused by a lack of centrifugal advance then it should improve with the lighter springs.