Build Marion Rising: 1974 FJ40 FST

[bugsnbikes]

I pumped A gallon of Muriatic acid into the block thru the water pump and into a bucket with a valve on the block drain hose so that I could let the Muriatic sit in the block for 5min prior to emptying into the bucket and then re-pumping into the block via a cheap 12v pump. I did that cycle 3-4 times and was quite happy with how much gunk the clear acid had picked up. when all was said and done......I was able to get in behind the 6th cylinder lower block area with the coat hanger and loosen up some more rust welded debris in the lower end of the block passages.

By the looks of it.....the Muriatic did wonders for both the block and the old radiator. however....I ended up switching to a new radiator.

make sure the kids aren’t around and wear latex gloves and eye protection and do this outside on a windy day. Muriatic acid is nasty stuff but does the trick.

 

[74fj40]

Could it just be residual oil burning off from all the cleaning/maintenance you’ve been doing? How long have you let it run for after all the work you did?

 

[MadMace]

Could it just be residual oil burning off from all the cleaning/maintenance you’ve been doing? How long have you let it run for after all the work you did?

I am happy to see you post that. That is what I was/am hoping--seems too simple though--i.e I'm usually not that lucky. I did use some degreaser and also some Kroil here and there to loosen up some tight bolts. The air rail needed a little as I recall to get it off.

I let it run for approx 5 minutes total--got it up to temp then started adjusting the carb. As I was working on the carb I saw the white smoke coming up from those areas. The new fan moves a significant amount of air so it was hard to see at first but when I shut her off, I could see it billowing up from there.

I shut her down for the day to query this forum before proceeding. I don't want to do any damage. I am tempted to run her a little longer tomorrow to see if the smoke continues or diminishes.

 

[74fj40]

I’m not convinced it overheated. I have an F155 in my cruiser and also had some blocked coolant passages on the drivers side around 5 and 6. I got it hot multiple times before pulling the head off and cleaning it out. These are tough tough motors.

If your not comfortable with letting it run longer than 5 minutes, just do multiple 5 minute sessions while letting it cool in between. If it stops smoking after awhile then you know if was just residual burning off! You can always use an infrared thermometer to check for over heating rather than relying on the factory gauge.

Got my fingers crossed!

 

[MadMace]

Up early today to work on Marion--not because I'm an early bird but I'm trying to beat the heat.

I think that I figured out the white smoke. The nuts on the valve cover were not as tight as they could be--I tightened those down and have not seen any more white smoke.

I still cannot get her to idle. She runs at approx 1/4 choke but when I push the choke all the way in, she dies. I was adjusting the screw that adjusts the throttle arm and noticed that the screw is not making contact with the throttle arm--I included a picture below. This would certainly account for why she dies when I push the choke all the way in.

How do I get the adjusting screw to contact the middle of the throttle arm?

 

[65swb45]

That’s not the screw you need to adjust Dean. The idle speed screw is at the very base, hidden behind the linkage you’re playing with. It threads directly into the cast iron base of the carb.

 

[65swb45]

FWIW, I had a mysterious smoke episode on my 45 a few weeks ago. Mine was at the back of the collector of the exhaust manifold right above the exhaust pipe.

I started hypothesizing all kinds of scenarios, then decided to just drive the truck some more and see if the dark stain on the throat of the manifold went away.

It did.

Don’t know how the stain got there in the first place.

 

[65swb45]

And the screw you’ve pointed out only contacts the other piece of linkage when the engine is off. It is the throttle positioner, and holds the throttle cracked open during startup. Then it’s supposed to move out of the way.

 

[MadMace]

Mark, thanks again, as always you are very helpful.

Is the picture below the right screw--I suspect it is as I do not see any other screws there.

I am trying to follow the FSM and obviously I am not following it well. You probably had the throttle position screw set to the right position so I likely have moved it out of position. How do I set the "First Idle Opening Angle" that is referred to in the FSM with the carb installed. From what I read in the FSM, I have to set that angle prior to adjusting the throttle positioner.

 

[65swb45]

I can’t tell from your pic.

 

[MadMace]

I was able to see that screw threading through the cast iron base so I am sure that is the idle speed screw. By adjusting it I am able to get her to stay running with the choke completely open but she dies unless RPMs stay above 750 RPM. I cannot get her down to the 450-500 rpm that the threads I have read recommend getting down to to do carb adjustments.

I have confirmed timing is set to 10 BTDC. I have not been able to identify any vacuum leaks (with the air filter off, if I cover the top of the carb with a piece of cardboard it dies immediately).

I have tried to follow the FSM--honestly, it is not very helpful. I have read different threads and I am making little headway. What is the best order to go in to get her idling at 650 smoothly?

 

[65swb45]

Get a vacuum guage. It helps eliminate WAGs

 

[MadMace]

I apologize for my naivety, but what are WAGs?

 

[Geezer Cruzzer]

I apologize for my naivety, but what are WAGs?

Wild Ass Guess!

 

[MadMace]

Ha!! Awesome. Yes, I need as much help as I can get there!

 

[thebigredrocker]

If you go out to buy a vac gauge, get a long chunk of tubing. That way you can run the gauge in the cab if needed.

Curious what distributor you are running and have you gone through it yet? Did you try twisting the dissy back to 7°, to get idle down?

 

[MadMace]

I have included a picture of my gauge and how I hook it into the brake booster line.

If I am hooking it up in a way to get a good vacuum reading, I must have an intake leak. At 1000 rpm it is a little under 15 and when RPMs drop to around 700 it is about 11. Being at approx 600ft elevation, these are terrible. For the life of me though I cannot find where the leak is. I have used a water bottle and sprayed all around the intake manifold, PCV, etc and there is no change in engine rpms.

I have also included a picture of the dissy I am running--I think it is the original one. I have not yet turned it down to 7° BTDC.

I guess the first thing that I have to do before I do anything else is get my vacuum up, correct?

 

[65swb45]

Ok then. As @thebigredrocker asked, what are the specs on dizzy point gap and dwell? Last time valves were adjusted?

RFG has a way of inducing valve seats to migrate, and subsequently over-tight valves make vacuum drop.

 

[MadMace]

I have not yet gone through the dissy--mainly because I am not educated currently in checking point gap, dwell, etc but I am going to have to learn and dive into it. Would this be a good time to upgrade the dissy vs digging into the one currently on there?

I adjusted the valves a few months ago. They needed significant adjustment but surprisingly it did not seem to make much difference in vacuum.

 

[thebigredrocker]

Your ported vaccum tube has something on it now, correct?

I’d be curious what Mark’s Off Road thinks about eliminating the VSV for now? Looks like you still have it partially hooked up.