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2G can i daily a mechanical fuel pump?

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TheFlashDSM

Supporting Member
1,082
311
Feb 18, 2010
stony brook, New_York
can i daily a mechanical fuel pump?

im currently in process of mount my aeromotive mechanical fuel pump, i think i saw some where that you need to run an extral cooler for the fuel if you wan to daily a high pressure mechanical fuel pump?

is this true?
can i run a mechanical fuel pump daily without a cooler? or do i need something else?
 
I don't think it was fair to put the guy down like that, he was just asking a general question about something. He wasn't saying it's better or will go faster than a car with an electric one.

One of the clear advantages of mechanical fuel pumps (which is why they're also widely used on heavy duty vehicles to this day), is because it's reliable. Less electronics that can go bad, and the connection between the motor wanting more fuel is direct, by belt or chain. You can also modify a mechanical pump just as much on a gasoline like on a diesel.

However, I'm also curious as to why would OP really want to run a mechanical gasoline pump on a DSM. If it was a diesel block, maybe. As for daily-ing it, I don't see why not. Gasoline fuel pressure is in the 40-50 psi range, whereas diesel pumps go up to 29,000 psi and more.
 
To actually answer your question. Yes. Yes you can. I would follow the manufacturers recommendations for inspecting the pump. My Waterman still looks brand new on the inside I just send it to get the shaft seals replaced once every couple years.
 
It will wear out is the main concern, mechanical race pumps aren't going to go the miles that an electric will, also you will have to figure out a way to prime the car when its shut off for any length of time, and as mentioned maintenance is required and the manufacturers wont sell replacement parts, they make you send it in for repair.
 
I would sell it. The Walbros are so cheap and reliable.
I mean 2 Walbro 525’s is moving SERIOUS amounts of fuel. Let alone 3 of them parallel. Or two parallel / series setups where 2 lift to 2 more inline (4 pumps total). I mean we’re talking 1500-2000 hp at that point.
I keep seeing people using multiple multiple Bosch units. I get it, almost unbeatable reliability. But the 525 blows it away.

Have you looked into Aeromotive fuel pumps!?!?
almost no reason for the hassle of mechanical pumps nowadays unless dedicated track car.
The reason for going mechanical pump (other than the flow) was usually to AVOID running a cooler I thought.

The cooler isn’t for the pump directly affecting the fuel.
It’s for the massive amounts of heat you’re transferring from the engine to the fuel and fuel tank by circulating so much fuel. It almost turns into a cooling system for the engine roughly once the engine is hot and the fuel components are heat soaked.
Hopefully the next bit makes sense on why the fuel gets so hot:
The fuel (particularly in surge setups) is returned directly to the pickup point. In the tank the return goes in the sump, in surge setups it goes RIGHT into the surge tank. The pump’s gonna suck a lot of that ‘already been circulated fuel’ and pump it straight back to the engine. Well guess where some of that fuel is coming back to? The surge tank. Where it’s gonna get pumped back to the engine, where it’s gonna come back to the...........
That’s why you run a cooler. Don’t run one unless you find out you have to. If you’re running ethanol you SHOULD be using something measuring content. Get the one that measures temperature as well like the Innovate unit.
 
The bottom line is that YES, I could daily mine, I drive it wherever I want to including to the shootout and back and you could daily one too, but its a matter of weighing the cost and benefit of using it in that way, only you can answer that.
 
Side note. If you’re not keen on having the mechanical pump in the bay.
There is a way of adapting a drive (like 3/8” or hex or something) to oil pump? and running a cable to the rear of the car.
Most notable car I’ve seen of late do that was the Mazzei Formula RX-7.

I have no experience w/ mechanical fuel pumps though, nor do I intend to ever have any for a while at least.
 
welp this post escalated quickly LOL i currently have a mech. aeromotive fuel pump for my car. it will be mainly for the track but once in a while driven to a car show or local around town. im well aware i can make my goal of 800-1000 on electrical fuel pumps, but i dont want the failure of one to ruin my expensive motor LOL i was going to run a second feed line with a walbro 190 inline pump to use to prime the mechanical pump so i didnt need to use a sure tank.

fuel to be used E85+R 117

i mean an answer is out there somewhere right?
 
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I run the Aeromotive and have for years, I prime mine from the in tank pump, then use a secondary straw in the tank for the pump to suck on once the engine is running and the pump is up to the task or drawing fuel, there is a check valve in that straw to prevent the in tank pump from pushing fuel back through it, you will also want the mechanical fuel pump type of fuel pressure regulator and at least two return lines back to the tank, if your using the stock return line sized lines, just run the stock return plus another one next to it back to the tank.
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I run the Aeromotive and have for years, I prime mine from the in tank pump, then use a secondary straw in the tank for the pump to suck on once the engine is running and the pump is up to the task or drawing fuel, there is a check valve in that straw to prevent the in tank pump from pushing fuel back through it, you will also want the mechanical fuel pump type of fuel pressure regulator and at least two return lines back to the tank, if your using the stock return line sized lines, just run the stock return plus another one next to it back to the tank.
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finally someone who can really help!!! okay how did you mount that pulley to the cam gear? bc i have a belt driven one too!

and more details on the second pump set up please!
 
finally someone who can really help!!! okay how did you mount that pulley to the cam gear? bc i have a belt driven one too!

and more details on the second pump set up please!
That allen bolt running through the center is an old stock head bolt, I knew it would be the right strength because the grade was high enough to be used as a head bolt and it worked fine, the pump needs to run at camshaft speed 1/2 crankshaft speed, so I bought a pulley from Summit Racing that had the same tooth count as the pulley that came with the pump, the three small allen bolts through the pulley are bolted to the cut off end of an old camshaft, that camshafts end has the stock location pin in it, I inserted that pin into the cam gear pin opening on the outside of the cam gear to not only properly locate the new pulley dead center but to lock it into the exhaust cam pulley so it wouldn't slip.

You defiantly need to do some drilling and tapping and finding out how to mount your cog gear to the cutoff cam piece, I just stuck it in a drill press at work and drilled and tapped it for some 6mm allen bolts, its really up to whoever does things how they want to mount the stuff, I just came up with an idea and made it work for me personally, working with what I had and knew I could get, I'm positive that there are other ways of doing it. As far as my other pump, its just the Walbro 255 that was already in my tank, I use it as a primer/pusher pump that runs always when the engine runs like it always did, except it feeds the inlet of the mechanical pump instead of the oem fuel rail that's all, knowing that the mechanical pump would likely want more fuel at times than the electric pump could have sucked past it, I put another an -6 tube into the sender that runs to the bottom of the tank through a bulkhead fitting, it comes out of the top of the sender and then runs up to the pump also, under the car near the front floorboards there is a Y fitting where the two meet (stock pump output line and the new line) and there is a check valve installed so that they both can feed the inlet of the mechanical pump but the electric pump can't feed back to the tank through the new an -6 tube that's in the tank, that's all, pretty simple LOL.

Also take note of the Aeromotive fuel pressure regulator for mechanical fuel pumps that is mounted on the firewall, this is the one that you will need to allow enough fuel volume to flow back to the tank if you plan to maintain 42-50 lbs of base fuel pressure, and you need to run at least two fuel return lines to the tank from it or one big 1/2"" line I suppose would work too.
 
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That allen bolt running through the center is an old stock head bolt, I knew it would be the right strength because the grade was high enough to be used as a head bolt and it worked fine, the pump needs to run at camshaft speed 1/2 crankshaft speed, so I bought a pulley from Summit Racing that had the same tooth count as the pulley that came with the pump, the three small allen bolts through the pulley are bolted to the cut off end of an old camshaft, that camshafts end has the stock location pin in it, I inserted that pin into the cam gear pin opening on the outside of the cam gear to not only properly locate the new pulley dead center but to lock it into the exhaust cam pulley so it wouldn't slip.

You defiantly need to do some drilling and tapping and finding out how to mount your cog gear to the cutoff cam piece, I just stuck it in a drill press at work and drilled and tapped it for some 6mm allen bolts, its really up to whoever does things how they want to mount the stuff, I just came up with an idea and made it work for me personally, working with what I had and knew I could get, I'm positive that there are other ways of doing it. As far as my other pump, its just the Walbro 255 that was already in my tank, I use it as a primer/pusher pump that runs always when the engine runs like it always did, except it feeds the inlet of the mechanical pump instead of the oem fuel rail that's all, knowing that the mechanical pump would likely want more fuel at times than the electric pump could have sucked past it, I put another an -6 tube into the sender that runs to the bottom of the tank through a bulkhead fitting, it comes out of the top of the sender and then runs up to the pump also, under the car near the front floorboards there is a Y fitting where the two meet (stock pump output line and the new line) and there is a check valve installed so that they both can feed the inlet of the mechanical pump but the electric pump can't feed back to the tank through the new an -6 tube that's in the tank, that's all, pretty simple LOL.

Also take note of the Aeromotive fuel pressure regulator for mechanical fuel pumps that is mounted on the firewall, this is the one that you will need to allow enough fuel volume to flow back to the tank if you plan to maintain 42-50 lbs of base fuel pressure, and you need to run at least two fuel return lines to the tank from it or one big 1/2"" line I suppose would work too.


the fuel part i understand just fine for the lines, im gonna run mine the same way.

that cam gear tho has me scratching my head, i must of read it 20x LOL i cant seem to make a picture in my head of what you have done with the cog pulley to the cam pulley. anyway you can post up some mre pics of the fuel pump and cog gear set up please?!!!
 
the fuel part i understand just fine for the lines, im gonna run mine the same way.

that cam gear tho has me scratching my head, i must of read it 20x LOL i cant seem to make a picture in my head of what you have done with the cog pulley to the cam pulley. anyway you can post up some mre pics of the fuel pump and cog gear set up please?!!!
The aftermarket cam gears have the location pin drilled all of the way through them, I needed a way to make sure that my fuel pump cog would be centered perfectly so as not to wobble, also I needed a way to keep it from just spinning on the face of the aftermarket cam gear, just bolting them together and sandwiching them would let the two slip, there is a lot of force driving that pump, more than you think, so I knew that I needed to pin the two part together not just bolt them together and being that the aftermarket cam gear had the pin hole all of the way through I took advantage of that pin hole, now I needed a pin to fit the hole perfectly that would be super strong, the stock can pin is perfect for this, its strong enough to run the camshaft, it will be strong enough to run the fuel pump.

I also needed a way to space the fuel pump drive cog away from the camshaft cog a little, I brainstormed and decided to take an old stock cam and chop the end off that has the pin in it, just the part thats where the camshaft seal rides (the polished area) is what I cut from the stock camshaft, I took that part and drilled all of the way through the threads in it so that a stock head bolt would slide through it, then I took that piece and flipped it over and inserted the pin into the aftermarket camshaft cog with the cut off end facing out of course, so basically you now have the two cam pins facing each other inside of that aftermarket cam gear, its as if you have two cams facing each other with the aftermarket cam gear in the center of them, get it? except on is a cut off end from a cam not the entire cam, and I then put the headbolt through the cut off cam piece and into the real camshaft, this now gives you a perfectly centered piece coming off of the exhaust camshaft to bolt anything that you would want to onto it.

I then needed a way to mount my drive cog for my pump, so I removed the cut off piece of stock camshaft and took my fuel pump drive cog from Summit and put them in a drill press and drilled three equally spaced holes through both of them evenly by bolting the two together temporarily while I drilled them, I then unbolted the two after removing them from the drill press and tapped the three holes in the fuel pump drive cog to accept 6mm bolts and I was then able to bolt the cutoff cam piece to the fuel pump drive cog and know that they were in perfect alignment, I then decided that I needed a big thick washer to go on top of the fuel pump drive cog so I found a big washer and used the fuel pump drive cog (with the three holes in it) and used that as a guide to drill the big washers holes to line up perfectly with everything, I then was able to take that used head bolt and run it through the entire washer/fuel pump drive cog/cut off piece of camshaft and run it in to the exhaust camshaft and bolt the entire assembly on to that camshaft knowing that it was all perfectly aligned.
 
wait i think i found it ------ 210l050 timing belt, i just bought this

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Those belt come in different lengths, yes I do have one in that length, I'm not sure if thats the length currently on the car though but I know I have bought that part number for sure, the L050 is the 1/2" width L style belt if I remember right, it will depend on how much length you need, I experimented with two of them to get it where I wanted it, one ended up being 1/2" shorter than the other I do remember that, there is a company that makes a Kevlar heavy duty version that I plan to put on and keep the current Gates one in the trunk for a backup.

Correction, after looking at the picture, yes I am currently running the 210L050, you got it.
 
The mount is homemade, its actually the old engine lift bracket from the intake side, the cast iron piece.
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I don't think it was fair to put the guy down like that, he was just asking a general question about something. He wasn't saying it's better or will go faster than a car with an electric one.

One of the clear advantages of mechanical fuel pumps (which is why they're also widely used on heavy duty vehicles to this day), is because it's reliable. Less electronics that can go bad, and the connection between the motor wanting more fuel is direct, by belt or chain. You can also modify a mechanical pump just as much on a gasoline like on a diesel.

However, I'm also curious as to why would OP really want to run a mechanical gasoline pump on a DSM. If it was a diesel block, maybe. As for daily-ing it, I don't see why not. Gasoline fuel pressure is in the 40-50 psi range, whereas diesel pumps go up to 29,000 psi and more.

Put down? Soft much? Heavy duty stuff runs a mechanical pump because it's diesel, and it was easier for a mechanism to do the timing vs electronics on old diesels. Modern ones use mechanical to make high pressure, because it takes a lot of power to run them, and it must be cheaper that way. Electrical can be just as reliable. How many vehicles go down the road 100k+ without a problem. Aftermarket raceing electrics suck because they do not have warranty dollars to worry about.

welp this post escalated quickly LOL i currently have a mech. aeromotive fuel pump for my car. it will be mainly for the track but once in a while driven to a car show or local around town. im well aware i can make my goal of 800-1000 on electrical fuel pumps, but i dont want the failure of one to ruin my expensive motor LOL i was going to run a second feed line with a walbro 190 inline pump to use to prime the mechanical pump so i didnt need to use a sure tank.

fuel to be used E85+R 117

i mean an answer is out there somewhere right?

your description there is not daily driving. That's race car use level. If your grandmother can't take it to the store, it's not a daily. Also if you really make 800-1000, and use it, you will ruin several expensive motors. There is a big post on ecmlink forums on this exact topic. A mechanical (well any front mounted pump really) can have a hard time drawing fuel from the tank. Has to do with vapor pressure. You probably would be best off with a surge tank. Or a rear mount cable driven mechanical.


The bottom line is that YES, I could daily mine, I drive it wherever I want to including to the shootout and back and you could daily one too, but its a matter of weighing the cost and benefit of using it in that way, only you can answer that.
What does your fuel temp do on a long drive?
 
Put down? Soft much? Heavy duty stuff runs a mechanical pump because it's diesel, and it was easier for a mechanism to do the timing vs electronics on old diesels. Modern ones use mechanical to make high pressure, because it takes a lot of power to run them, and it must be cheaper that way. Electrical can be just as reliable. How many vehicles go down the road 100k+ without a problem. Aftermarket raceing electrics suck because they do not have warranty dollars to worry about.



your description there is not daily driving. That's race car use level. If your grandmother can't take it to the store, it's not a daily. Also if you really make 800-1000, and use it, you will ruin several expensive motors. There is a big post on ecmlink forums on this exact topic. A mechanical (well any front mounted pump really) can have a hard time drawing fuel from the tank. Has to do with vapor pressure. You probably would be best off with a surge tank. Or a rear mount cable driven mechanical.



What does your fuel temp do on a long drive?
Fuel temp hangs around 20-30 degrees over ambient, on an open highway (shootout) in town they can get ridiculous not ideal but not as bad as with a surge tank.
 
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