Mefi 3 base timing

S

steeler85048

New Member
Jun 30, 2013
11
Peoria
Boat Info
1984 SeaRay Monaco
Engines
305 chevy
I have a 230 Searay signiture bow rider with a 5.7 TBI motor and a Bravo 3 outdrive. I just recently repowered it with a long block and swapped everything over to the new block. My question is this, What should the base timing be? I put a paperclip into terminals 1 and 2 on the DLC plug and it
would not start until I advanced the throttle a little. IT then proceeded to idle around 1,000 rpm. I used my timing light and tried adjusting the timing with the distributor but the lowest timing I could come up with was 22 deg. what more, I left the timing light hooked up and took the wire out of the DLC plug and it idles at around 660 rpm at 22 degrees. I took it out on the lake after adjusting to best idle not in service mode and it rant fine up to 3900 rpm where it bogged out a little under full throttle. Just a bit less than full throttle it ran fine. But would not get above 4,000 rpm.
 
My throttle body cover says 8 deg BTDC but I could not even come close to that without killing the motor.
 
It’s been a long time since I touched an engine with a distributor but could you be off by a tooth?
 
Put #1 cylinder on tdc of compression stroke. Check where the rotor is pointing. Pull up dist. Have the rotor pointed at # 1 cylinder and slowly drop it in. Align oil pump shaft of you have to. You should be all set to fire it up. If it cranks slow or backfires though the carb retard just a little bit. Get it started set idle and then check with light
 
I did all that to get it started. The engine fired right up and runs fairly well just drops off at around 4,000 RPM at full throttle
 
Oh ok does it like break up or just not want to rev anymore no spark no fuel what is your best guess
 
Could be electric issues
 
it acts like it isn't getting enough fuel but it should still rev higher than 4,000
 
Has it always been like that, or did it just happen
 
steeler85048 said:
it acts like it isn't getting enough fuel but it should still rev higher than 4,000
Click to expand...
No; this is incorrect.
If it is only getting enough fuel for 3950, it will never see > 4k.

Detroit has been trying to accomplish that since 1973, and has yet to do so.
 
Well, not sure what to do from here. I guess I could add a booster pump from the tank to the fuel filter to boost the amount of fuel getting to the cool fuel pump. I put a brand new pump on right before dropping in the motor because I didn't want to have to change the thing with the engine in the boat as its really difficult to get to...
 
Yeah, I agree, I can get it as low as 22 btcd but that's as low as it will go. So, not sure what the issue is but the distributor was dropped right and I checked it several time when I was dropping it and again after. I'm sure if it was that far off it wouldn't start. This is the harmonic balancer that was on the old motor and both are vortec block, heads and cam.
 
I think I'm gonna try an inline high volume/pressure holley inline fuel pump inline between the tank and the filter to see if that rectifies the falling flat on its face.
 
Did you verify fuel pressure at 4k? I would do that before another pump.

Did you verify the timing mark on the balancer is correct with tdc?
 
Steeler, I was not meaning to imply that your problem was fuel related rather then timing (although it could be), but rather that statement was incorrect.

Not that I'm out to correct everything, but especially when in the diagnostic mode, sometimes an incorrect assumption leads to immeasurable time and energy being expended fruitlessly. Later, when/if you do have a fuel related issue you will get further, faster by realizing that statement was in error.

I agree with Scoflaw on all counts. It seems to me like your timing ain't what it should be. If the new crank is keyed differently than the former one, your balancer marks and/or TDC would need to be redone. If that is all the same, perhaps you didn't stab the dist as effectively as you meant to.

As Scoflaw pointed out, there is little sense in chasing low fuel pressure until that has been confirmed to be the case, which it may very well not be.
 
Put crank on tdc and with the plug out of no# 1 cyl use a little piece of wire or screw driver and see if piston is at the top of cylinder
 
I am considering that as nearly impossible with the engine now in the boat. I did this already with the engine on a stand and the mark lined up correctly with the distributor and the cylinder.
 
Is there a relative number timing wise that the MEFI3 would set the timing to while idling? Maybe this way I could get an idea where it is by marking it and then timing it with the engine in service mode. Also, I was curious if the engine should be at exactly 1200 rpm in service mode or is 1,000 normal/acceptable?
 
If you can get the number one spark plug out which is number one closest to the front of the engine on your right side facing the motor You should be able to get something in there to see where the piston is I'm not trying to complicate your problem just trying to help you find answers
 
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