Chrysler 1978 6hp Model 62B8J

[Big Jay]

Hey guys, was ready to trade out my 6 hp Chrysler for a snowmobile here and took it to test it and make sure I wasn't ripping the guy off. Turns out I was.

She's running only on 1 cylinder but will catch the second at high RPM sometimes... I've rebuilt the carb as best I can without a kit (no parts available) and it's all ok there. I also replaced a plug boot as it was missing the clip inside and had just a wire dangling.

This model has a stator under the flywheel, so I don't know if there are any points to check for cleanliness or gap?

She seems to be wasting a lot of fuel too when not at high RPM.

I've also noticed upon repeated trails the bottom cylinder is the culprit with a "wetter" plug than the top. Yes the top isn't burning right either.....

Any help for this noob would be greatly appreciated.

Thanks guys ~!

 

[Big Jay]

Re: Chrysler 1978 6hp Model 62B8J

Here's a few pic's of the unit in question...

 

[wickware]

Re: Chrysler 1978 6hp Model 62B8J

1. What colors are the sparks at the plugs on your spark test?

2. What is the compression in each cyl? Without a gauge you s/n be able to hold the compression in with your finger or thumb.

3. Did you totally disassemble the carb, inspt, adjustments out, force can carb through ?all ports? to verify them open?

4. Is there a separate fuel pump and did you disassemble, inspt diaphragm and etc?

5. Age/cond of fuel? Good tight fuel conn? Was the eng stored with untreated fuel and how long?

6. Past history of engine and last time it ran 100%? A few questions and ideas that might help.

Your Honesty In The Trade Is Appreciated. I?ll see your Thumbs Up Later Today!

 

[jerryjerry05]

Re: Chrysler 1978 6hp Model 62B8J

New plugs?
Change the packs around and see if the spark changes position.
Change all the wire ends.
If you've cleaned the carb.It will get fuel to both cylinders.
Check the fuel pump diaphram.
Possible it's bad and flooding the draw cylinder.
Water in the fuel?Change tanks.

 

[Big Jay]

Re: Chrysler 1978 6hp Model 62B8J

1. What colors are the sparks at the plugs on your spark test?

2. What is the compression in each cyl? Without a gauge you s/n be able to hold the compression in with your finger or thumb.

3. Did you totally disassemble the carb, inspt, adjustments out, force can carb through ?all ports? to verify them open?

4. Is there a separate fuel pump and did you disassemble, inspt diaphragm and etc?

5. Age/cond of fuel? Good tight fuel conn? Was the eng stored with untreated fuel and how long?

6. Past history of engine and last time it ran 100%? A few questions and ideas that might help.

Your Honesty In The Trade Is Appreciated. I?ll see your Thumbs Up Later Today!

Thank you for your response, I'll try to answer as best I can:

1: I have spark on both cylinders, I'm turning it over myself and can't quite tell the color while holding it against the head. I am however picking up a proper spark tester today and will get back to you in good time.

2: Compression was 119psi and 120psi with a proper tester.

3: Totally disassembled the carb and inspected it it. Removed the only adj. screw and sprayed my cleaner (Johnson/Evinrude Engine Tuner) through all the openings and ports, it seemed to go through everywhere.

4: I have yet to check the fuel pump. My concern is if I mess up the diaphragm I can't get parts for this motor. I thought if the one cylinder was getting fuel it might be ok... ?

5: Fuel is fresh this month, mixed right (50-1) and the engine was in storage for a few years, but I cleaned the carb bowl out when I stored it.

6: As far as it's history goes, it's anybody's guess really. It belonged to a Lodge owner who had it for years and never ran it once. He got it from a client in trade for a cheaper rate. The client is supposedly a marine mechanic who "said" it ran well. When I first started it in a test tank, I found the prop shaft was cracked, it would only shift into forward. I had the shaft rebuilt since then and now this....

Hope this helps. I'm waiting for the wife to return from work with my spark tester to check color (I live 20 miles in the bush)

Thanks again for your reply...

 

[Big Jay]

Re: Chrysler 1978 6hp Model 62B8J

New plugs?
Change the packs around and see if the spark changes position.
Change all the wire ends.
If you've cleaned the carb.It will get fuel to both cylinders.
Check the fuel pump diaphram.
Possible it's bad and flooding the draw cylinder.
Water in the fuel?Change tanks.

I put new plugs after finding out the wrong ones were installed, but I was worried about switching the packs around, wouldn't it fire backwards? (probably a stupid assumption) I have changed one plug boot, which wire ends are you referring too? The wires on the harness?

 

[Big Jay]

Re: Chrysler 1978 6hp Model 62B8J

Hey Jerry,

What would I be looking for in a bad fuel pump diaphragm?

 

[wickware]

Re: Chrysler 1978 6hp Model 62B8J

IMO until Jerry gets back:

1. Jerry might be referring to a hard or cracked diaphragm (very possible with ethanol).
2. I like to see good action in my pumps glass bowl when I?m pumping my primer bulb.

Question to Jerry related:

1. Will the pump openly pump fuel into a jar vs carb if cranked to prove it?s working?
2. Will you see movement in the glass bowl if equipped if the pump is working?

 

[Big Jay]

Re: Chrysler 1978 6hp Model 62B8J

Well guys, I finally got my spark tester and it's worth it's weight in gold.

After using it, the bottom cylinder (No2) proved to have weak white spark for the first pull then nothing after. The top cylinder (No1) was consistent bright blue spark. So I though crap, the power pack is shot. But while trying to make sure I had good contact within the boot and not succeeding, I removed the boot and realized things looked pretty old. The spring with the spike in it was shiny, but the hole in the cable where the spike was driven in looked stretched out and the wire itself a dark dull grey. So I re-spliced the cable and drove in the spike to a fresh hole and retested. I now have bright blue spark on both cylinders.

I guess it's easy to read to much into a situation when things go wrong....

My next question (I created a new thread too after many searches) is what do I re-torque my flywheel to?

 

[wickware]

Re: Chrysler 1978 6hp Model 62B8J

My Clymer shows 17 ft lbs but that needs to be confirmed by other?s specs.

The spark tester sounds encouraging. The funny part is I have one but has not had a need to use it. LOL! I had planed to use it on a mower while I had whatever warranty from Harbor Freight. The old open tester or a plug has gotten me through spark issuers since the early 70s.

I hope the spark solver the issue. Good Luck!

 

[Big Jay]

Re: Chrysler 1978 6hp Model 62B8J

My Clymer shows 17 ft lbs but that needs to be confirmed by other’s specs.

The spark tester sounds encouraging. The funny part is I have one but has not had a need to use it. LOL! I had planed to use it on a mower while I had whatever warranty from Harbor Freight. The old open tester or a plug has gotten me through spark issuers since the early 70s.

I hope the spark solver the issue. Good Luck!

Thanks wickware!

I hope so too lol. I won't find out til tomorrow though, can't get to the lake til then. I will post my findings. Good idea about the gas line in a jar thing, great way to test a fuel pump. Love it, and will probably use it eventually

 

[jerryjerry05]

Re: Chrysler 1978 6hp Model 62B8J

1. Will the pump openly pump fuel into a jar vs carb if cranked to prove it’s working?
2. Will you see movement in the glass bowl if equipped if the pump is working?


#1 Yes it should pump fuel as you turn it over.
These pumps are very low pressure so they won't pump much but will pump.
#2Yes if there is gunk or anything in the bowl you should see movement.

When I said change packs around I meant to put one in place of the other.
It shouldn't fire backwards unless you put it in upside down
Glad It was a simple fix!!!

 

[wickware]

Re: Chrysler 1978 6hp Model 62B8J

Thanks for the info JJ! Can you or anyone confirm the 17 or 40 ft lbs on the flywheel?s torque (I saw in my Clymer Manuel)? With a straight edge 40 ft lbs looks closer (aligned in the manual) and sounds better.

""Big Jay, I would suggest this is confirmed before testing vs causing another problem.""

As little as 17 could cause a problem or damage if it should be 40

 

[Big Jay]

Re: Chrysler 1978 6hp Model 62B8J

Hey Jerry, I'll have to try the jar vs carb trick and get back to you on it.... It doesn't have a glass bowl though...

Wickware I believe you might be right. I need to confirm the torque spec on the flywheel nut before wrecking something else.

When I find out, I'll post it for sure

 

[wickware]

Re: Chrysler 1978 6hp Model 62B8J

1. Good Catch I Hope, on the flywheel?s torque. I?ll add some lines across to help align spec after blowing info.
2. Have you serviced the impeller lately??

 

[Big Jay]

Re: Chrysler 1978 6hp Model 62B8J

Ya, I think the torque should be ok. I had the impeller out while repairing the prop shaft and it looked good. No cracks and not overly bent up. So I reused it. Hard to get parts for these guys anyway.

 

[jerryjerry05]

Re: Chrysler 1978 6hp Model 62B8J

F429065 Boats . net Chrysler/Force part# $13-14

If it's set for a while it should be changed.Good re-sell point!

 

[Big Jay]

Re: Chrysler 1978 6hp Model 62B8J

You're likely very right, thank you for the link!

I am still however having troubles with running on only one cylinder. It seems to be running a bit better but it's still intermittent. I can only assume it's the ignition wiring because that's what I played with when it began running a bit better. I still haven't tried the fuel pump test though, maybe try that next too....

 

[Big Jay]

Re: Chrysler 1978 6hp Model 62B8J

I just managed to buy a couple of huge barrels, and plan to make one into a test tank. That will make things much easier to troubleshoot at home.