I have a 1988 Dodge Dakota, it came with a v6 but my friend's uncle who i bought it from had put what he said was a "boat engine" in the Dakota. It seems barely used and it appears to be a 318 to me, I have no real clue what year it is.
My issue though is my fuel pump stopped working about 5 months ago as I was driving. I knew before hand the engine was getting starved intermittently.
I put on about 3 brand new mechanical fuel pumps, no difference. I started using an electric one I got from an '89 Dak but it just never meshed up. Either it pumped too hard or the regulator didn't regulate down enough or the carb would overflow even at the lowest setting.
I got it running today, a bit of overflow, I had to keep my foot on the gas the majority of the time, and if its not cranked up successfully in the first one or two turns it kills any battery I put in it. Sometimes I get five. I have to turn the light switch I have fired to the pump on for a few seconds to feel the carb.
What I want to know is:
1. how does one check a cam shaft to see if its so worn it can't operator a mechanical fuel pump?
2. Is it even common for cams to get so used they just get worn down and cant reach the arm anymore on the pump?
3. How much do I have to remove to switch these cams out? I am getting in too much trouble breaking my cars down where I live and need to kinda rap hings up quick. Is it as simple as unbolting the engine mounts, jacking the engine up, taking the oil pan off and pulling it out?
4. I have found several new camshafts in my price range but they have different numbers. One says "318 360 .441"/.441" Lift 6901" while the other says "SB LA 318 360 .420"/.442" Lift 6900 (Fits: Dodge)"
and I wonder what that means, what the specifications on my camshaft are and if I can just interchange these camshafts and it work? Or is timing altered? I am just tired of dealing with the constant autowork and the excess gas use, and the fiddling with light switches and wiring and hoping the battery doesn't die.
Get a common aftermkt low pressure electric fuel pump and install/wire it correctly. No regulator required and sure beat the h@ll out of pulling the front and top off an engine.
Fuel pump lobe wear is getting to be more common as the oils available are junk. Don't protect from direct rubbing forces.
I dont know if the fuel preassure is a factor in the float clip in the carb not keeping it shut. if the preassure is low enough I guess the carb will feel up to that point, close th clip, and the excess fuel still being pumped will return to tank. I don't want the trouble of having to switch that light switch button and waiting though. I want everything to be mechanically in sink I guess I am saying.
I guess its not possible to buy the lobe? Eitherway I want to look in this engine so I'd still appreciate any input on the cam shaft switch job.
I found some fuel pressure pumps with low PSI. This one from 2.5 to 4.5, and from 5 to 9 PSI but I do not know how low PSI needs to be and both of their mesh charts claim an '88 Dak is not compatible with their pump. I think it is but I still don't know which PSI is good enough to supply this carb? I don't know what I would use as a return line since this line is going strait to the carb unless the preassure is so low it just doesnt keep force on the gas in the line and won't force the float clip in the carb open.
This motor does not have a lobe on the cam for the pump. It is a part (round offset stamped steel) that bolts to the front of the timing gear - called a fuel pump eccentric.
so do u think i can get to that easily to get my mechanical pumps back working? why do u think they stopped working anyways? i looked at the markings on the 3 new pumps and seen they weren't covering but a 3rd of the tip of the arm of the new pumps but i do not know how relevant that is.
I just want it back to '88 standards and '88 specs, no more rigging or ad ons.
To get to it, you would need to pull apart the front of the engine. There will not be much contact on the fuel pump arm. Sounds like you have more issues than a fuel pump if a stock pump is making the carb overflow. You need to clean out the lines and carb. What is on there for a carb? If you really feel there is too much pressure, put a guage on it. 88 Dakotas did not come with V8s, (exception of Shelbys). Chrysler did not put V8s in until I believe '93 (newer style). Someone put it in, so find out what the engine is.
Its a 318 that came out of a boat supposedly. i dont mean the stock pump i meant the electric pump which i got out of an '89 dakota. Thats technically stock but not mine. I mean when I had the original mech pump in it worked fine, then didn't work as good, then finally stopped working period. When I put 2 or 3 other brand new mech pumps from the autostores in they would not suck really. I felt a very very small suction on my finger, thats it. But I know on my old Dodge Ram D250 van that it had the same 318 wit that same general chrystler mechanical fuel pump. The '89 elec pump is making the carb overflow, the lines are very clean, the carb is clean, rebuilt by a pro, the fuel preassure gauge I got didn't help much but maybe its lowest psi settings were bad? I couldn't even get the return to work on the regulator. Like I said though I want to just nip this in the bud and return this 318 to using a mechanical pump.
The 89 pump is for fuel injection. It will be WAY too much pressure. The regulator would need to have a return line to the pump to make that pump work. That pump will not allow pressure to be controlled by an external regulator - it would have to have a return line - just like fuel injection works in those trucks. If you got a simple a/m pump, you would not have that issue. If you got a good mechanical pump for a 318 (older modle), you should be ok - as long as that engine has a carb. What carb is it - 2 barrel?
its a one barrel carb, carter i believe. im not sure if my mech pump had the long arm or short one since ive not taken it out in a few months but i know i got the right one at the store when i replaced it. I have in the past gotten bad mech fuel pumps from O'Reilly's but I got 3 replacements for this mech pump on this 318 "boat" engine and im not sure if buying an older mech pump for a 318 is gonna help, thats my concern and I want to at this point just deal with the mech pump so it will drive like it was when I first got it with no stalling, no overflowing, no reaching for light switches, no killing the batteries due to excess cranking. Is there an easy way to analyze and figure out why the mech pumps arent working?
That must be an old motor - dont remember 318s being in boats, but it should be basically the same. No reason for having a bad pump, never really came across that issue. It should not take much to fill that carb. You may want to check out the carb and make sure its not filled up with gunk. Also, when the pump is put on, take the fuel line off by the carb and turn it over and see if gas will spray out (into a can). Make sure the pump is primed first. It is not uncommon for a pump to go out, but then again its not a very common thing either.
My friend exaggerates alot too. I amm going to get the numbers off the motor to put its age and origins to rest though. like i said the suction on the pump was there but very soft, the same on the other 2 or 3 new ones. i had them go directly into a jar beneath it and it didn't have enough suction to empty it. the carb has been rebuilt by this ******* oracle I know so I trust the carb with my life lol. I still cant help but wonder if the eccentric was warped when that motor mount broke and my fan ate my radiator. I will confessed the new mech pumps weren't primed though. That is why I was also curious if the eccentric, t chain replacement, and sprocket replacement was tantamount to nipping this issue in the bud? Those 3 items I am willing to put money on/in.
Not knowing a LOT more about the engine, I cannot be certain, but I'd be concerned that the ProProducts pump shown would be a little bit light @ 28 GPM. Carter makes a simple electric internally regulated vane pump (regulator not required) that will pump up to about 72 GPM also at about 4-6 PSI. Check out Carter Universal Rotary Vane Electric Fuel Pumps GP4070 - SummitRacing.com
Edit: Note that if you find it necessary, this pump can be further regulated with an in-line (non-return) regulator.
thx Pat and Greg, so do you two also think if I get a low enough PSI unit that theres no way the carb will flood or overflow? Like is the psi so low that even if its left on a return line won't be needed and the clip on the carb flots holding back the needle tip at the end of the fuel line that goes up front won't be forced opened or anything?
A stock fuel pump should be just fine - no need for special mods with this simple setup. Are you sure your pusing the pump lever far enough to test it - they push VERY hard - probably need to hold it in a vise. The pump eccentric is oblonged to make the pump work - and must be on because that would also hold on the timing gear - unless for some reason it came loose (not tightened correctly when put on). The pump will/should prime itself when the engine is cranking over. Test the output into a can and if it is pumping, the gas will pump into the can. If it pumps in, I would think the fuel issue should be fine unless there is some blockage. ??
Yea I know there is no blockage I cleaned those lines really good and probably about ten times. I didn't use a vice but I thought I should had put it in somethinng and put some real force on that arm. I'll inspect the eccentric, and the t chain and its gear. I'll just replace them all anyways just to be replacing I guess. I definitely can't spend 81 dollars on an elec pump though but those other parts might need replace because like I said the motor mount did break in the past leading to a bad ride and my fan eating my radiator.
An electric pump at 6 PSI is just like a mechanical pump at 6 PSI. The carb will behave the same way it would with a good factory mechanical pump. I'm not sure about the P.P. pump mentioned before my post, but the Carter I mentioned does not require a bypass type pressure regulator. Other, similar looking Carter's might require a regulator in your application, but the one mentioned will likely not require a regulator at all. If there is an issue with your carb using this pump, the issue is almost certainly with your carb. I know that isn't what you want to hear, but I do believe it's what you need to be told.
Good luck with this. I hope that you're able to get your truck's issue resolved.
how does one check a mechanical fuel pump externally? Would I just need to buy a brand new pump and put it in and if it doesnt work that means the eccentric is messed up which means my old pump is probably still good? I really need to just find a way to test the pump while its out period because a 25 dollar pump is going to bite into my budget and I need to know what I can avoid buyin or what I can take back to recoup some losses.
Although it is not common to get a bad pump, you could get one. Clamp the pump in a vise and put your finger on the inlet side, then push the pump lever (very hard). You will feel the pull on your finger. If you have it in the truck, spin the engine over (dont start it) and put the fuel line in a can and see if it is pumping the fuel.
oh yea i know now that it needs like 4 or 6 psi. i have bought I think 2 bad ones brand in the past thats just why I had been paranoid about it.
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