Builds Salt wagon My first fj40 (build) (1 Viewer)

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Don’t give up on the 2F yet.
Not given up yet but I think If this one throws a rod or something catastrophic happens I am not sure which direction I will go. At the end of the day the most fun I have is driving the 40. a B series diesel was another direction I wanted to go in.
 
Not given up yet but I think If this one throws a rod or something catastrophic happens I am not sure which direction I will go. At the end of the day the most fun I have is driving the 40. a B series diesel was another direction I wanted to go in.

I struggle with this.

I love driving my 40 with the original engine. If it blew up tomorrow I would have a really hard time not swapping a modern v8 in. I have some of the key parts already.
 
How much are radiator caps these days $20. Holding vacuum and holding pressure are two different issues. Helium can pass threw glass even tho it is a larger atom than Hydrogen that can't get threw that same same glass.
 
I struggle with this.

I love driving my 40 with the original engine. If it blew up tomorrow I would have a really hard time not swapping a modern v8 in. I have some of the key parts already.
Right its a worthy conversation. I really wanted the fj40 original but to a certain point and the end of the day I want to drive it. Ideally I would put some sort of deisel in it with a 5 speed trans. if I had much more time and money - I have always said a 1kzt and 5 speed manual would be one of the coolest motors in a fj40. if it can move a big heavy prado it can move a 40.

I could swap back in my v8 now I would just need to buy motor mounts. But I pulled that motor for a reason. it leaked like a strainer. every gasket needed replacing. but it ran well. I am curious if that engine has been rebuilt. My students will be tearing into it tomorow I am curious on how the internals look on the old 307.

but I would use a marks adapter and probibly bore the engine over. and use a sniper kit. and use the 4speed transmission I have.
 
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How much are radiator caps these days $20. Holding vacuum and holding pressure are two different issues. Helium can pass threw glass even tho it is a larger atom than Hydrogen that can't get threw that same same glass.
they are pricey now. I seem to remember a few years ago a cap was 8 dollars. I purchased one from redline. seemed to be the cheepest oem price. but I am sure one could be found cheeper. I am almost thinking air got in the system some how. Ill be sure to test and report back once I get the rest of the things I ordered in.
 
I know I am relieved on the compression numbers and the consistency this time. Not great high numbers but what I would expect from a non bored out block from 1978. I am not seeing any glaring issues that point towards a head gasket in terms of the compression numbers. Yeah no oil in coolant, no coolant in oil, only coolant coming out of overflow, No blow by under the valve cover, Not seeing steam out exhaust although smoke at start up that I always attributed to vavles seals. Smoke seemed grey. The thermostat works. The cold uper and lower radiator hoses I am not sure why but yes. I will say the drive I did was not long enough to warm the engine up. less than a mile going 25mph. Witch is why its kinda weird. I am wondering if something is blocked the coolant at the thermostat housing or close to it. seems to flow there though. Or maybe I just never had it fully bled? I ran it all summer in very hot conditions without issues though.

Goal today is to fill the block and radiator with that thermocure stuff that should arrive today. then drain it tomorrow, refill with coolant and burp using the burp funnel.
IMO - your compression numbers are well within spec. Below is the range per 2F FSM.

Upper is 149. Low limit is 114

Picture from FSM for 2F
IMG_8953.jpeg
 
If you do go back to a sbc, find a 350. I not familiar with them, but maybe an LS.
 
If you do go back to a sbc, find a 350. I not familiar with them, but maybe an LS.
Yeah I think That might be the plan whenever this engine gives up the ghost. I dont think I would go LS. Hopefully that will be some time from now though.
 
Let’s all calm down with the engine swap talk…
Hahahah yeah! I already did one to put the 2f in! No worries. Just thinking about a plan if anything happens to the 2f. I am thinking about looking for a fj80 with a blown up 3fe then swapping in a SBC or somthing. I see that there is a cool adapter that Advance has for the autoboxes in the fj80s. I really miss my fj80. it was great.

Is it evident that I like taking things apart and projects too much?
 
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Another update:

I filled the cooling system with the thermocure stuff to see about cleaning the block. Used the burp funnel off amazon (Feel dumb not buying one before its great) Let the 2f sit at high idle for about 10 minutes while it was burping and it never overheated and it stayed at operating temp.

I am willing to admit it might be the radiator cap... the only other thing I can think of is it was not burped correctly and the air bubble just finally let go. But I did use the 40 all summer for 4 months before this happened. Or maybe I just have to put a load on the engine to have it start to over heat. I am going to drive it around the block before I drain it again.

After work today I am going to drain the thermocure and refill with coolant and do the same process with the burp funnel.

Another update - next week I will be replacing the plugs and valve seals. I have all the tools now. going to borrow a compressor to keep the valves from dropping.
 
Another update:

I filled the cooling system with the thermocure stuff to see about cleaning the block. Used the burp funnel off amazon (Feel dumb not buying one before its great) Let the 2f sit at high idle for about 10 minutes while it was burping and it never overheated and it stayed at operating temp.

I am willing to admit it might be the radiator cap... the only other thing I can think of is it was not burped correctly and the air bubble just finally let go. But I did use the 40 all summer for 4 months before this happened. Or maybe I just have to put a load on the engine to have it start to over heat. I am going to drive it around the block before I drain it again.

After work today I am going to drain the thermocure and refill with coolant and do the same process with the burp funnel.

Another update - next week I will be replacing the plugs and valve seals. I have all the tools now. going to borrow a compressor to keep the valves from dropping.
You didn’t mention it so I will:
I recommend flushing out the Thermocure with copious amounts of hose water than do a distilled water flush before coolant.
Unless you have gnarly mineral heavy tap water then flush with distilled a couple times.

Curious to see what that first and subsequent flushes look like, mine were brutal.


Left is initial dump, got it running clear after.
Right is first dump after Thermocure.
IMG_8548.jpeg
 
The compressor trick is ideal on the valve springs and seats.
I almost lost a valve in the cylinder, by accidentally pressing down on a valve stem with my homemade (angle iron-lever) spring compressor. Pressure was lost in the cylinder, but I might have been lucky, perhaps the piston was up far enough allowing me to retrieve the valve, as it didn't drop past the top of the valve guide. Perhaps you can turn the crank so that you can see the piston at a top position thru the spark plug hole, for each cylinder, and then you don't have to worry about loss of air pressure, and dropping your valve all the way down into the combustion chamber?

Also, I dropped a keeper into a push-rod hole. I used a magnetic tool to retrieve the keeper, then lost the tool in the hole. I finally got it them out, but, it was quite a bit of messing-around. My advice is to stuff rags in the push-rod holes, and oil-fill / PCV-hole, to prevent fugitive spring-keepers from derailing your day. In my shop, I employ basket-type coffee filters in place of enormous, yet absorbent paper towel rolls, for most jobs - wiping, polishing, etc. they save valuable space. Also, I used a magnet to retrieve the keepers once the springs were compressed, instead of gambling with caffeine and small parts.
 
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You didn’t mention it so I will:
I recommend flushing out the Thermocure with copious amounts of hose water than do a distilled water flush before coolant.
Unless you have gnarly mineral heavy tap water then flush with distilled a couple times.
I did a bit more searching. A quick web search suggest that chlorine, and chloramine (more of a modern treatment used in tap-water), employed as a disinfectants in tap-water, is bad for rubber-seals, plastic, and can corrode metal. So, it is more than minerals making scale-deposits. Perhaps that is why the radiator caps loose elasticity at their seals? Or, a hose clamp connection that starts to leak, months, or years later?
 
I did a bit more searching. A quick web search suggest that chlorine, and chloramine (more of a modern treatment used in tap-water), employed as a disinfectants in tap-water, is bad for rubber-seals, plastic, and can corrode metal. So, it is more than minerals making scale-deposits. Perhaps that is why the radiator caps loose elasticity at their seals? Or, a hose clamp connection that starts to leak, months, or years later?
I’m a low hanging fruit kinda guy 🤷🏽, but I can imagine chlorine not being great too.

Good call.
 

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