A second FDC, why not

[wolfmangk]

I understand that-but the FDC is there for a reason. I.E. Manipulate one or two valves and it operates if the engine is running poorly, or whatever, without replacing hoses.

 

[rdixiemiller]

I bypassed my FDC because it was leaking lots of fuel (4 gallons in 8 hrs) into the oil pan. I hooked up a pyrometer when I did the bypass, WAY too hot! It would hit 1400 on a level road in 3rd gear! So I started backing it off. Ended up backing the fuel rate 3 full turns before I got it under control. It will hit 1100 quickly on a hill, then ease up to around 1150-1175. I have some used motor oil in the tank, so I will run it out and benchmark it with straight diesel.
It runs stronger than it did before the bypass, but I will caution anyone doing this to install a pyrometer!
I picked up 2 different ones on E-Bay for less than $20 each. I rounded up a K thermocouple for $8 or so. I started off with my Fluke 87V ($30 at a pawn shop) since I know it is accurate to a few degrees, and has an extremely rapid response. It would have been really easy to fry my turbo if I hadn't been checking.

 

[cranetruck]

......
I picked up 2 different ones on E-Bay for less than $20 each. I rounded up a K thermocouple for $8 or so. I started off with my Fluke 87V ($30 at a pawn shop) since I know it is accurate to a few degrees, and has an extremely rapid response. It would have been really easy to fry my turbo if I hadn't been checking.

The digital display will give you a much more rapid response than the analog display.
I used the Fluke DVM at first because I had all parts on hand, but after installing the dial pyrometer it was obvious that the needle movement averaged the reading. The peaks are still there, but don't show up.

 

[Latrine_Commander]

Plain cover on PSB-6a

The plain cover is common on all non-military versions of the PSB-6A pump. There is even a wheeled farm tractor (a White) that uses the LD/LDS engine. The FDC was only on the 465 engines. It was not on the LD-427's. If you find an LD-427 in old M35 series. You can get the cover and the wedge from it. Most of the time you will find them in engine containers as they are take offs.

John

 

[jimk]

I have a question... Via manually actuated valves, or electronically actuated ones-what about making some extra plumbing and having a bypass/non bypass situation at the flip of a switch or lever(s)? So you can have the performance and non leakage of a bypassed FDC, but the ability to run gasoline or keorsine without wrenching on the engine? Is the fuel delivery adjustment absolutely neccesary?e]

The problem with a FDC switching system is the main fuel adjustment nut needs to be re-adjusted each time there is a change (about 2 turns). This adjustment is critically important as adding more fuel increases boost (LDT's and LDS's) and EGT(Exhaust Gas Temp). Too much fuel can damage the engine and/or turbo. JimK

p.s. You can still run other fuels without a FDC. It's fuction is to provide equal power output with different fuels.