cerial Posted February 17, 2018 Share Posted February 17, 2018 I have an 88 mj that is going 350 Chevy. Entire truck has been stripped electrical wise and is being upgraded. The 350 engine is carb with standalone efi being a option later. I have the fuel tank that runs down the drivers side. I have the 88 tank and sending unit and I am using a external Walbro to feed the throttle body with a return line running back to the tank. I want to eliminate the current in tank pump completely. Leaving just the sending unit in there which will run a speedhut fuel gauge. I am looking at installing a non efi fuel pickup like this; https://www.ebay.com/itm/1986-1987-Jeep-MJ-Comanche-18-23-5-gal-gas-tank-sending-unit-/391892643149?rmvSB=true But before I drop$75 plus locking ring/gasket and make a $100ish mistake plus down time to get other parts. I would like to know if there are any differences like baffles inside the tank or the locking ring being a different size between the 86/87 tanks and the 88-92 tanks. The tank I have has some heavy tank protection that basically welded to the frame around the fuel tank. Unless the thing is leaking I really want to avoid swapping it out any time soon. That being said if this pickup ring is say 1/4" smaller then the other one. I might consider just replacing the 88 tank with a new 86 one so everything goes in as I have planned. Thank you for any advise and help. Link to comment Share on other sites More sharing options...
DirtyComanche Posted February 17, 2018 Share Posted February 17, 2018 You can probably just pull the pump put of your current tank and put a piece of tubing in its place. You'd probably still want a pickup sock on it, but it shouldn't be too hard to build something that would work. Are you using the Walbro external pump to feed the carb then? If I was you I'd order up a Holley Sniper and save myself the time of changing out the current pump. Link to comment Share on other sites More sharing options...
Eagle Posted February 17, 2018 Share Posted February 17, 2018 That listing doesn't make sense. All the 87s were fuel injected. For '86 the 2.8L had a mechanical fuel pump on the block feeding the carburetor, but the 2.5L had throttle body injection. The part shown in the listing looks like it might work, but the listing is incorrect. Link to comment Share on other sites More sharing options...
cerial Posted February 17, 2018 Author Share Posted February 17, 2018 23 minutes ago, DirtyComanche said: You can probably just pull the pump put of your current tank and put a piece of tubing in its place. You'd probably still want a pickup sock on it, but it shouldn't be too hard to build something that would work. Are you using the Walbro external pump to feed the carb then? I want to avoid any rubber anything in the tank that would be submerged in fuel. Just install the pickup and I won't need to touch the thing unless the send unit goes out which is not something I see happening any time soon. Yes, I am using the Walbro to feed the carb. Actually the High pressure/flow Walbro feeds a 3 quart surge tank till full up to a point then a return line runs back to the main tank. The surge tank feeds a Low pressure mechanical pump and the engine. When I go fuel injection the 3 quart surge tank will have it's own inline fuel pump at lower pressure/flow then the main tank one with a return to the surge tank allowing me to kill the main tank pump and run off that 1/2 a gallon or so during the stupid angle stuff. Nothing I can do about the thing running out of oil. But this thing is just meant to run 200-250hp junk yard engines so I don't hurt the ax15. If I toast one I can throw in another and have the thing up and running that weekend. 26 minutes ago, Eagle said: That listing doesn't make sense. All the 87s were fuel injected. For '86 the 2.8L had a mechanical fuel pump on the block feeding the carburetor, but the 2.5L had throttle body injection. The part shown in the listing looks like it might work, but the listing is incorrect. That's what has me confused. It might work. I am thinking it probably will work. But I just don't know about these to say it will without a doubt be the same. I'm ordering all this junk now while it is in the 20's so I can have everything ready once it gets closer to the 50's as this build is outside. It would really be a kick to the head if I put the thing up there and find out it is smaller then the efi one. Link to comment Share on other sites More sharing options...
DirtyComanche Posted February 17, 2018 Share Posted February 17, 2018 35 minutes ago, cerial said: I want to avoid any rubber anything in the tank that would be submerged in fuel. Just install the pickup and I won't need to touch the thing unless the send unit goes out which is not something I see happening any time soon. Tubing doesn't mean rubber hose. Braze, silver solder, or TIG weld it together, depending on what you can do and what material you go with. Or if you use hose make sure you get the submersion rated type. I'd have to hunt down the spec but it is about a 20 year life in fuel, so it doesn't cause issues. Guys have issues because they use regular FI hose, it will fail relatively shortly if submerged. Link to comment Share on other sites More sharing options...
HOrnbrod Posted February 17, 2018 Share Posted February 17, 2018 15 minutes ago, DirtyComanche said: Or if you use hose make sure you get the submersion rated type. I'd have to hunt down the spec but it is about a 20 year life in fuel, so it doesn't cause issues. Guys have issues because they use regular FI hose, it will fail relatively shortly if submerged. https://www.kaizenmotorsports.com/blogs/news/11743001-e85-and-correct-fuel-hoses Link to comment Share on other sites More sharing options...
cerial Posted February 18, 2018 Author Share Posted February 18, 2018 I want to avoid having any air enter that main pump shortening the life as much as possible. It is only a $100 or so pump and I will carry a spare later on just in case to be able to change it in a lot or campsite if need be. But I want to avoid any kind of restriction or air entering that pump if at all possible and see this line as a possible weak link. I could sleeve my current or a new factory sending unit. Freeze a pipe and heat the other before sliding the 2 pieces together then solder the ends before putting 10psi into the new line to check for leaks. This is plan B as I don't like the idea of having any hose inside the fuel tank and any clamps or any possibility of air entering the line if I can avoid it. But if the one in the above link would work there is no need to have this sleeved section as it is one tube from ring to sock. The only difference I can seem to find in the mj tanks is that the 86/87 ones did not have the slosh plate. But That should not matter with the pickup right? It is the same basic bends. Correct? Link to comment Share on other sites More sharing options...
Jeep Driver Posted February 18, 2018 Share Posted February 18, 2018 This is the one you want, NOS. https://www.ebay.com/itm/NOS-86-Jeep-Comanche-Fuel-Tank-sending-unit-assy-23-5-gallon-tank-52003652/232057535509?ssPageName=STRK%3AMEBIDX%3AIT&_trksid=p2060353.m1438.l2649 Link to comment Share on other sites More sharing options...
cerial Posted February 27, 2018 Author Share Posted February 27, 2018 Thank you for the help Link to comment Share on other sites More sharing options...
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