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Discussion Starter · #81 ·
Its the wax motor type with a 12v input. Thanks for the great pics and explanation. I will get this wired up when the air temp sensor I ordered shows up. It looks amazingly easy to wire too.
 

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The wax motor type does not use the air temp sensor like the solenoid version, It uses a special sensor mounted below the intake plenum. That one turns on when temp reaches the preset level where the one used for the solenoid turns off when the preset level is reached. The wax motor sensor is part 3915945 shown in photo #1 and mounts as shown in photo #2. It is also sometimes mounted in a port near the rear of the head. Here is a diagram showing the location. Cold Start Timing Advance System (KSB) Temperature Switch (005-069) In case you need it the wiring harness for the wax motor unit on a 4bt is part 3918364. Part #2 in diagram below. This is out of the Cummins manual. In case you have a weak heart that wiring harness is very expensive. Lists for around $225 so you can go from there.
 

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Discussion Starter · #83 ·
Alrighty meow!

I built my engine mounts for the truck after struggling to get the engine and bruce jenner mated together. Who knew if you put a little lube on the tip, it helps slide right in! Ok, enough dirty.

IMG_20210422_155520 by Paul Abbott, on Flickr

IMG_20210422_155527 by Paul Abbott, on Flickr

IMG_20210422_155538 by Paul Abbott, on Flickr

I used some polyurethane pucks that I had laying around for another project that never materialized so I cut them down to 1" thick and stuffed them in there.

IMG_20210422_165932 by Paul Abbott, on Flickr

Another shot with my beautiful alternator bracket on there.
IMG_20210422_165948 by Paul Abbott, on Flickr

And it's final resting place.
IMG_20210422_165918 by Paul Abbott, on Flickr

Obviously I have a lot of crap left to do, but the hardest part is done in my opinion.

I have to figure out the downpipe/exhaust situation, coolant plumbing stuff, battery cable/alternator wiring and intercooler stuff. I already stripped down an extra wiring harness I had to get the gauges in the dash to work. I am going to leave the computer hooked up and just pull the cluster's check engine light.

But for anyone who wants to know, this is a 1995 F150 with the 4.9L six and I did not have to swap out engine stands at all.
 

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Your engine mounts look fine but you'll probably notice a good bit of transferred vibration. The 4bt is a shaky little devil. Angle type mounts were used in the Ford E350 vans with the 4bt but they weren't too concerned about vibration. The best engine mounts for these things comes from a company named Lord. They make mounts for aircraft and also some vehicles. Below shows their mount. Their main drawback is they are expensive. Anchor makes a similar mount that's about 1/10 the pri
 

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Discussion Starter · #85 ·
Your engine mounts look fine but you'll probably notice a good bit of transferred vibration. The 4bt is a shaky little devil. Angle type mounts were used in the Ford E350 vans with the 4bt but they weren't too concerned about vibration. The best engine mounts for these things comes from a company named Lord. They make mounts for aircraft and also some vehicles. Below shows their mount. Their main drawback is they are expensive. Anchor makes a similar mount that's about 1/10 the pri
Definitely! Especially since I am using a pretty high durometer polyurethane. If it becomes unbearable, I will figure something else out. I have room to go up higher if I want too so maybe legit rubber that's 2" thick might be helpful. I will cross that bridge when I get there!
 

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Discussion Starter · #86 ·
I think I need to reindex the throttle blade. I have run out of idle throttle adjustment and playing with adjustments isn't really helping that much. I read that it is common to miss that when doing the governor springs and I certainly might have forked that up. What makes me think this is that I have to hold the throttle open a bit to get the idle up and smooth out. I just know its not right.

Oh, I got the thing fired up and moving under it's own power. I hooked up a separate fuel supply and jury rigged a throttle cable and moved it to a different spot in my driveway. Vacuum pump works great because I had brakes. Power steering DIDN'T work because the reservoir is dry. Whoops!

I don't have a drive belt yet so no water pump turning, but I did get the water necks figured out and hoses hooked up. I had to neck down both the inlet and outlet at the engine. My thought process was that it is easier to find hoses for common vehicles and I can always replace the water necks later if I was so inclined. I used galvanized steel pipes welded to the housings and beads built up around the tips so a hose has something to grip on to. Its nice having a welder.
 

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Lots of the B series Cummins engines used in commercial trucks had metal pipes for the radiator plumbing. They just had a short rubber hose at each end. That way they could just carry a piece of hose in the glove box in case for repair. That hose was very high grade stuff made by Gates and is a bit pricey.
 

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Discussion Starter · #88 · (Edited)
So I was out getting the cooling system bled and ran into a weird problem with the engine: All of a sudden the engine started running probably around 2000 RPM no matter where the throttle is at. When I disconnected the fuel shut off solenoid or tried to shut it off with the truck key, the truck would idle down and just sit there and hover at idle. The only way to get the truck to stop running was to pull the fuel line out of my temporary tank. Any ideas what could cause this?

Oh, and after the engine was at operating temp, the idle oil pressure dropped to 35 psi. Very pleased with that too.
 

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Have you been adjusting the fuel output on the pump. Sounds like you were getting close to runaway. Also, does your pump have a mechanical shut down option? If so, that should shut it off if the electric isn't working. Have you changed the governor spring? That also can cause issues if it's not installed correctly.
 

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Discussion Starter · #90 ·
Have you been adjusting the fuel output on the pump. Sounds like you were getting close to runaway. Also, does your pump have a mechanical shut down option? If so, that should shut it off if the electric isn't working. Have you changed the governor spring? That also can cause issues if it's not installed correctly.
Hey Charlie. I started a new job so I have not been able to get out there and record what is going on. I also had to replace my cheap lift pump because even though it was new, it stopped functioning properly. I replaced it with an Airtex pump and it fired right up.

So yes, I did install a 3600 governor spring. But that was before I even started the engine at all. So the previous video in this thread shows it running. I reindexed the throttle lever to get the idle up a bit as I am 99% sure I didn't do it right when I installed the gov spring the first time.

But this is what is happening now.
 

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Didn't know there was a 3600 RPM governor spring. Was aware of 3200, 3800, and 4200. Most guys stop at 3200. That was really weird with the pump sitting there idling and the solenoid disconnected. I couldn't tell from your video but does your pump have a manual shutdown option? If it does you could use that and forget the electrical part. You have to remove the solenoid, take out its plunger, and put the gutted part back in the hole. Then you just have a push/pull cable in the cab. Which Airtex pump are you running? Just be sure it has enough flow and not too much pressure. There is an optional mechanical piston type lift pump for the VE injection pump which is pretty much fool proof. It's just a tad expensive. Around $375 for all the parts.
 

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Discussion Starter · #92 ·
Didn't know there was a 3600 RPM governor spring. Was aware of 3200, 3800, and 4200. Most guys stop at 3200. That was really weird with the pump sitting there idling and the solenoid disconnected. I couldn't tell from your video but does your pump have a manual shutdown option? If it does you could use that and forget the electrical part. You have to remove the solenoid, take out its plunger, and put the gutted part back in the hole. Then you just have a push/pull cable in the cab. Which Airtex pump are you running? Just be sure it has enough flow and not too much pressure. There is an optional mechanical piston type lift pump for the VE injection pump which is pretty much fool proof. It's just a tad expensive. Around $375 for all the parts.
My pump doesn't have a manual shut-off arm. So I'm thinking the only way I can test it is by pulling the shut off solenoid and seeing if I can use some needle nose to shut the fuel off manually somehow.

And yeah, the governor spring is aftermarket.
 

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Aha, yes there are 12V and 24V solenoids. Same for the alternator, starter, and the VP30 injection pump that may have been on that engine. Most everything used in military was 24V as well as some marine and industrial applications. That Airtex pump appears to be the same as the factory units. The diaphragm pumps in general don't have the best reputation for long life. One gauge that can be on the option list is a fuel pressure gauge. VE pumps like somewhere in the 3-12 PSI range after the fuel filter. You lose a bit going through the filter. The piston model I mentioned usually has near 15 PSI pre filter. They even make dual reading gauges so you can monitor pre and post filter. Hewitt Instruments makes those which are mechanical so you'd have 2 fuel lines inside the cab. See photo. They did make VE pump with and without the mechanical shut down. You just have one that doesn't so the solenoid is your only option. Below is a photo showing the mechanical part.
 

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There is an optional mechanical piston type lift pump for the VE injection pump which is pretty much fool proof. It's just a tad expensive. Around $375 for all the parts.
Can be had for $100 less than that :)
 

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Figured out the problem. Damned 24v solenoid. Had no clue. I am going to order up a 12v solenoid tonight.
24v solenoid is not your problem. They work fine with a good 12v source & will out live a 12v solenoid. When power is disconnected, even with a 24v solenoid the plunger would drop & cut fuel &l shut down engine if nothing is hanging up the plunger. You might want to just take apart & inspect. Most likely a piece of debris is making the plunger hang up.
 
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Discussion Starter · #98 ·
24v solenoid is not your problem. They work fine with a good 12v source & will out live a 12v solenoid. When power is disconnected, even with a 24v solenoid the plunger would drop & cut fuel &l shut down engine if nothing is hanging up the plunger. You might want to just take apart & inspect. Most likely a piece of debris is making the plunger hang up.
I will give that a shot. I assume right off the battery is a good 12v source. I was wondering why it seemed to work just fine and then all of a sudden this scenario occured. Now that I clearanced the bracket that Charlie always talks about, I can pop the old one back in and see if its good. I will clean it a bit and give it a shot.

Thanks Mark!
 

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Mark, I believe the pump you sell is a modified version for the lower pressure and absolutely nothing wrong with that. The price I mentioned was for a OEM Cummins low pressure unit that was available on some industrial 4bts. That thing is horribly expensive.
 

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Discussion Starter · #100 ·
I went out and plugged the gutted 24v FSS back in and it was running like it did in the video: Nice and high with way too many revs. Had to pull fuel hose from the tank to stop it, as I expected.

Then I put the needle and spring back in the FSS and this time it shut off after pulling 12v from the terminal. So I must have had a teeny bit of debris holding it up.

I think I must have reindexed the throttle plate too far because that's the only explanation for the high revs. Now, what might have been contributing to my thought process of increasing the indexing was the failings of the previous lift pump. It literally required a lot of throttle to get it to idle properly. Of course that would be necessary if the faulty lift pump was not passing pure fuel and passing some air along with fuel. Now that I have a properly functioning lift pump, it doesn't need that much throttle to maintain the idle.

Because of this, I have pulled off the A/C bracket I made in preparation for reindexing the throttle plate back to where it was before. I may attempt to run the engine without the throttle plate on there at all and find the idle setting that is best. That is of course unless you guys think that would be disastrous. LOL

Thanks for your guys' help. I will report back the results when I get around to it.
 
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