Motor Help

[GRUNION]

I need some help. First off I have a EFI 502 with a pro charger. a few weeks ago I started loosing rpm. Now I can only get about 3000 rpm and it runs like its missing. and I think its pinging but not sure Im not a big motor guy. I have done a compression test everything is good I have replaced the cap rotor and plugs, Because we thought maybe it was fouling plugs I also took my computer over to az speed and marine to turn my cold start off. I was told to do this by Jim and a friend of mine Charley because with the pro charger it runs rich until it warms to 160. and with the procharger you dont run a thermostat so u never get to 160. also I found the vacum hose broke from the fuel pressure regulator to the manifold and I fixed that. today we ran the boat and it was the same 3000 rpm. We are thinking it might be a fuel pressure problem I have an aeromotive fuel pump and it sounds awfull. I was told you should barley hear them. tomorow morning we will check it when we get to the shop. But I was wondering if you guys have any other ideas. Or have had this problem.

[Lavey Huffer]

boost leak?
do you have a boost gauge?
does the EFI have any fuel pressure test port?
Those aeromotive pumps are noisy.
ping could be detonation(lean)
is it Direct fire ignition or run a distributer?

[GRUNION]

yes i hav a boost gauge and im getting boost.

[Lavey Huffer]

fuel pressure?

[GRUNION]

boost leak?
do you have a boost gauge?
does the EFI have any fuel pressure test port?
Those aeromotive pumps are noisy.
ping could be detonation(lean)
is it Direct fire ignition or run a distributer?
the efi has a test port i cant test it till i get to the shop no tools at home.
and its a hei style distributor

[Lavey Huffer]

fuel pressure test could help you figure out if it is or is'nt the fuel pump.
have you looked at the plugs to see if they are burnt clean?(lean)?

[Lavey Huffer]

also if your fuel pump is making more noise than usual it could be a dirty fuel filter.....boat sits all winter.....another poss.

[GRUNION]

also if your fuel pump is making more noise than usual it could be a dirty fuel filter.....boat sits all winter.....another poss.
filter is new so r the plugs old plugs were black. I do know a pressure test is in order. like i said cant do it till tomorow. Thanks for the help.

[Lavey Huffer]

No Problem
At This Point Is Sounds Like Fuel Problem

[GRUNION]

No Problem
At This Point Is Sounds Like Fuel Problem
sure hope so have havi plans for the weekend

[SmokinLowriderSS]

Don't rule out the ignition coil, the box on top of the HEI distrib. When mine quit 2 summers ago, 2500 was all that happened without bad missfire. Started from 3500 and got worse.

[GRUNION]

Is there a way to tell if the coil is bad without replaceing it?

[superdave013]

A blown engine that you can hear pinning is no good at all. And one that's lean is just as bad. Hope you didn't already melt her down.

[502 JET]

Dou you have a fuel water seperator?Look for water in your fuel.Water in fuel is a common problem due to condensation inside the tank.The boat will run great with no load but put it in the water and try and go and it will fall on its face.Pump some fuel into a clear container and see it it seperates.

[GRUNION]

OK first off thanks for the help. I wasnt able to fix the boat before the poker run but we went in a friends boat.
Second we found a few things out. My fuel pump was good but my pressure was at 66psi way to high it should be 44. I was also missing a knock sensor on my boat, so I put one on why anyone would take that off is beyond me. Then with a couple people we were able to track down the noise in my engine it was the timing chain or so we thought. You could actualy feel it hitting the cover. So we pulled the cover and found it had a half inch of play. So we replaced it and put it back together. not bad for half a day huh. Fire it back up and same noise :mad: .... So now im thinking I lost a lobe on a cam or a lifter is not flat. and forceing the cam forward. And now Im gonna have to redo all the work we did. At least the pulling everything apart stuff ,what a pain. I think I will have also ate up the distributor gear from the cam moving forward and back.....
Does anyone think I should run anything different than a stock cam? Remeber its a 502 with a procharger and lightning headers.

[BOOGEYMAN]

Contact Steve @ www.stevemorrisracingengines.com he is a great guy and will make you a custom cam for your app and ship it to you.
Travis.

[Lavey Huffer]

OK first off thanks for the help. I wasnt able to fix the boat before the poker run but we went in a friends boat.
Second we found a few things out. My fuel pump was good but my pressure was at 66psi way to high it should be 44. I was also missing a knock sensor on my boat, so I put one on why anyone would take that off is beyond me. Then with a couple people we were able to track down the noise in my engine it was the timing chain or so we thought. You could actualy feel it hitting the cover. So we pulled the cover and found it had a half inch of play. So we replaced it and put it back together. not bad for half a day huh. Fire it back up and same noise :mad: .... So now im thinking I lost a lobe on a cam or a lifter is not flat. and forceing the cam forward. And now Im gonna have to redo all the work we did. At least the pulling everything apart stuff ,what a pain. I think I will have also ate up the distributor gear from the cam moving forward and back.....
Does anyone think I should run anything different than a stock cam? Remeber its a 502 with a procharger and lightning headers.
Well I hope your motor is ok
do you have a flat tappet or roller?
You added a supercharger and headers to make it breathe better.An engine is really just an air pump and proper cam selection will help it work better,more air more power......

[GRUNION]

Well I hope your motor is ok
do you have a flat tappet or roller?
You added a supercharger and headers to make it breathe better.An engine is really just an air pump and proper cam selection will help it work better,more air more power......
its flat tappet but concidering switching to roller. Its a gen5

[Lavey Huffer]

I did a retro fit roller set up Comp Cams...hav'nt run it yet..all new motor..
the only bad thing I have read about is oil to the lifter bearings at idle...but they have a better design now and it is only a problem if it idles for a long time.

[GRUNION]

how much more hp do u get from a roller cam

[Lavey Huffer]

some where around 20 hp? less friction = more power

[GRUNION]

and how much more would it cost me?

[Lavey Huffer]

$300 cam +-
$350 lifters +-
push rods are a different legnth
valve springs....they usually run a different spring rate
do you have roller rockers?

[centerhill condor]

mo money... mo money...

[GRUNION]

I hear its pretty hard to get the cam timming reprogrammed in the computer so I think Im gonna stick with the stock one.

[Lavey Huffer]

how did you re map the fuel? for the supercharger

[GRUNION]

I dont know what Jim did when I took him my computer but he rattled off a bunch of stuff and I think that was one of them. But not positive.