225 Dauntless Lost power

[KcSolomon]

Hey everyone,
I need help once again. This time my 1970 CJ5 with a Dauntless 225 is losing power. It starts and runs fairly good. It takes a little warming up up then it idles like a dream. I went out of town for a week and when I got back and fired it up the first time it backfired a bit. When I drove it it had no power.
I have noticed that the oil pressure is a staying down around 40. Normally it would get up to around 60 while driving. that could be because of the loss of power. Another thing is backfiring when I first start it up.
I am a newbie when it comes to mechanics. If it were not getting spark or gas I could troubleshoot something. With this issue I am lost. My first guess is a fule air mixture. Please help.

Thanks,
KC

 

[JR74CJ5]

Before messing with air / fuel mixture, check for vac leaks, or exhaust leak (though you'd probably hear the exhaust leak if that... )

I say this assuming the Jeep ran good with power before going out of town, and just started doing this when you got back.

The timing, and fuel / air mixture would not have changed... Neither should have any vac lines or exhaust either, I get that... But... You also mention backfiring, which would lead me to the same conclusions.

Timing
Mixture
Vac Leaks
Charging system / low bat level, inopp alt (just a thought)
Points in distributor?
Exhaust leak at the heads

Where are we loosing power? And what exactly is it doing while loosing power? Bogging down? or simply no-going good while motor "sounds" normal?



~ JR

 

[BajaEdition]

check fuel delivery for a partially clogged line
look over the carb to see if it is working good

that was the easy part

checking the vacuum lines is a little messy but but well worth the time replacing them with new tubes is even better.

with the engine running, can you hear any hissing sound?

start engine with a timing light hooked up, use it to check if each spark plug wire is conducting.

is the distributor tight? or does it spin

check the timing

replace the ballast resistor, this could burn out the condenser if it went bad.

replace the spark plug wires and the spark plugs, gapping them to spec

, if non of that worked, we go for the distributor, what do the cap and rotor look like inside?

replace the condensor and try again.

next the points.

nowhere is the bad news, if nothing has worked, our carb is working fine and we just get weakpower, we have redone the ignition system and still get weak power, it is time to replace the ignition system, you see Kaiser for some reason chose to use a cheaply made distributor in that engine and it is problematic. The gears strip easily and it can wander or just not turn in time, and this can happen at any time.
there are several alternatives, you can get HEI Distrbutors for around 230 clams that are 1 wire rewires.
report back after all the test please so we can help more.

 

[hagar]

If you can get it to run, connect a vacuum gauge to the intake manifold.
You want a reading of 16"-18" of vacuum and a steady needle (at sea level), lower readings at higher elevations. Steady, not pulsating, needle is important.
Anything else and you could have valve/timing issues, exhaust, fuel,or vac leak problems.

 

[KcSolomon]

Before messing with air / fuel mixture, check for vac leaks, or exhaust leak (though you'd probably hear the exhaust leak if that... )

I say this assuming the Jeep ran good with power before going out of town, and just started doing this when you got back.

The timing, and fuel / air mixture would not have changed... Neither should have any vac lines or exhaust either, I get that... But... You also mention backfiring, which would lead me to the same conclusions.

Timing
Mixture
Vac Leaks
Charging system / low bat level, inopp alt (just a thought)
Points in distributor?
Exhaust leak at the heads

Where are we loosing power? And what exactly is it doing while loosing power? Bogging down? or simply no-going good while motor "sounds" normal?



~ JR

It's struggling to start. Turns over good but takes a long time to fire. Once it starts running it does not have any power. I don't have a RPM gauge but it sounds like it is running slower.
I checked the exhaust and found that two of the bolts had worked loose. I tightened them but it made no difference.
The battery is only a few months old. Both the battery and and alternator are working fine.
The only hissing sound is air being sucked in the air filter. I can't place any other hissing sounds.
There are no vacuum lines on my jeep. I don't have a vacuum gauge. If y'all think that a vacuum issue could be the cause I will purchase a gauge tomorrow.
A friend of mine has a timing light and is bringing it over tonight. We'll check the spark plug lines.
The distributor is tight. Somewhere along the line to me somebody changed the distributor for what looks like a Chevy distributor. I found this out from the guy I buy my parts from a few months back.
The spark plugs were replace over the summer. I gaped the to spec then.
Thank y'all both for all the ideas and instruction. I will keep you up to date on my findings.

Thanks,
KC

 

[67Jeepster]

If the timing marks are way off, stop - do not adjust timing yet. First you need to see if the timing chain has jumped a tooth.
1. Split firing order in half - 1-6-5 - 4-3-2 - the numbers are cast into intake manifold.
2. Take the valve cover off the head with the 4th cylinder (4)
3. Remove the coil wire from the distributor and bump the starter until the timing mark is approaching the timing pointer.
4. When the TDC make reaches the pointer, both intake and exhaust rockers should be moving. If they are not both moving, your timing chain has jumped.
5. Replacing the timing chain and sprockets correctly should put the ignition timing back in the correct location.
Running with the timing chain one tooth off will show loss of power, two teeth might barely run, three teeth may damage valves and pistons.

 

[BajaEdition]

Did you say the engine has no vacuum lines at all?
a 70 CJ should have a few, I could go out and count but it should have a couple to the carb and one to the distributor at least

 

[KcSolomon]

Did you say the engine has no vacuum lines at all?
a 70 CJ should have a few, I could go out and count but it should have a couple to the carb and one to the distributor at least

Let me correct myself. There is 1 line from the driver side valve cover to the carb. I can see where the vacuum line would connect to the distributor but there is no hose and if there were I don't know where the other end of the hose should be connected.

 

[JR74CJ5]

I can see where the vacuum line would connect to the distributor but there is no hose and if there were I don't know where the other end of the hose should be connected.

I believe that would be your Vac Advance...

What distributor has it been changed to? Is it a self contained HEI? or do you still have a functioning ignition coil?

The vac advance could very well be your problem, though I don't understand how it just started this loss of power after you returned from a trip...

 

[BajaEdition]

I have to agree, something is wrong here, that engine has a few vacuum lines that need to be hooked up to be able to have power, one to the vacuum advance is one, the one from the valve cover is a big hose going to the air filter, it is a smog device, PCV, but their are a few other lines. that need to be there.

 

[KcSolomon]

I have to agree, something is wrong here, that engine has a few vacuum lines that need to be hooked up to be able to have power, one to the vacuum advance is one, the one from the valve cover is a big hose going to the air filter, it is a smog device, PCV, but their are a few other lines. that need to be there.

This is my distributor. I was told by someone I trust that it is a Chevy distributor. You can see where a vacuum line would connect to it but there is nothing connect to it. Has not been since I purchased it a year ago.
the second photo is the only vacuum line installed. Could any of you tell me where to run each line to and from?

 

[JR74CJ5]

Hmmm...

Looks like a HEI GM style.

And def has the vac advance port.

I would tell you to get that hooked up, and that the carb should be hooked to intake vac, but I am not positive AND I still can not understand how it would have ran fine before but not now, and with no changes...

I believe you do need to fix that, but I think we should track down what has changed since it was running to now...

Baja: Does it look as if the vac advance port has been plugged in that first pic?

 

[BajaEdition]

I cannot say about the brand of Distib, but it is a conversions
their needs to be a vacuum line from that port to the carburetor however.
once that is on, and it is timed, it should have the power you want
now if there is something wrong in the spark system, you will have to find out what type of distributor you have and then you will have to troubleshoot it according to that, it is not a stock distributor, the stock distributor is a point and condenser style, that is an upgrade, if it is a Chevy, it is wrong, you need a Buick set up for an odd fire engine, no Chevy is going to fire correct and will definitely cause engine problems. Only a distributor set up for the oddfire Buick will work correctly

 

[KcSolomon]

I cannot say about the brand of Distib, but it is a conversions
their needs to be a vacuum line from that port to the carburetor however.
once that is on, and it is timed, it should have the power you want
now if there is something wrong in the spark system, you will have to find out what type of distributor you have and then you will have to troubleshoot it according to that, it is not a stock distributor, the stock distributor is a point and condenser style, that is an upgrade, if it is a Chevy, it is wrong, you need a Buick set up for an odd fire engine, no Chevy is going to fire correct and will definitely cause engine problems. Only a distributor set up for the oddfire Buick will work correctly

I have looked over the carb and don't see any point where I could connect the distributor. the photo's below show the carb from all 4 sides. I have found three points on the intake manifold where a line could be connected.
Once again any advice would be helpful.

 

[BajaEdition]

what carb is that?
it looks like a 2g, but it does not have the port for vacuum on the passenger side
maybe the a plate is missing?
but the stock carb on a Dauntless V6 will have a port on the front half of the passenger side of the carb on the bottom flange.
I do not see one on yours, so you either have some changed carb or missing a mounting plate that had it.

 

[KcSolomon]

So here is a game changer. With me not knowing what I have I decided to drive it over to a mechanic about 1/2 a mile away. On the way there the CJ backfired 5-10 times very fast and started running like normal. I drove it on down the road to where I buy my parts(Car Quest) and it drove fine the whole way. Started back up on the first couple turns and drove home fine.
I'm not the kind of guy to leave well enough alone. I dug through all of the paperwork that came with my jeep. stacks of invoices 10+ years old. I didn't find anything that told me what kind of carb I have. Any ideas about what to do or how to figure out what carb I have?

 

[BajaEdition]

KC sounds like you need a mechanic
I can do a lot of things, but I cannot take someone with no mechanical knowledge and trouble shoot their engine over the net
that thing has some serious problems form the pictures you posted, bring it to a mechanic and see what is needed.

 

[67Jeepster]

I agree with BajaEdition, its time for a mechanic. There may not be a vacuum port on your carb setup. On photo IMAG2702 there looks to be a crack in the smog hose right after the braiding ends. In IMAG2700 the gasket may be leaking between the pot metal of the carb body and the cast iron of the carb base. On my dauntless there is a vacuum port directly below the fuel inlet. I’ll try posting a photo.
Normal engines are even fire, the dauntless is odd fire.

Normal v-8: 1 - 2 - 3 - 4 - 5 - 6 - 7 - 8 fires every 90 degrees
Odd fire v-6 1 - 0 - 2 - 3 - 4 - 0 - 5 - 6 fires 90 or 180 degrees
Even fire v-6 1 - 2 - 3 - 4 - 5 - 6 fires every 120 degrees

If your distributor is even fire and engine is odd fire, you will always run bad.
There is the chance the engine been swapped out, check the serial number.

 

[BajaEdition]

yea but nothing sounds better than an odd fire warming up in the morning at camp while drinking campfire coffee.
Both my Jeeps have Dauntless 225s and they just sound great.