Twin 5.0 efi loss of power

Jeff, i see links on your list post. Any idea where that list resides on the internet?
 
I replaced water seperators and when i did i filled with 75% sea foam. Ran at 2000 rpm for bout 5 minyes. Great way to clean injectors. When i fill uo i use lucas oil fuel additive. Been good for now. Gonna change filters monthy now for this year
 
I replaced water seperators and when i did i filled with 75% sea foam. Ran at 2000 rpm for bout 5 minyes. Great way to clean injectors. When i fill uo i use lucas oil fuel additive. Been good for now. Gonna change filters monthy now for this year

What rpm are they turning now?
 
That's awesome. After my starboard repower my port side lags a bit. I pushed throttles to 100% today and the new motor spun up to 4800 while the port dragged along at around 3800-4000.

I'm doing distributor this week, it's what killed the other motor. Plugs, wires, cap rotor and coil are all new. It's due for a fuel filter change which could be restricting it since it's from last year. Do you think it was the seafoam that did the trick of a combo of everything?
 
Combo of everything. Cool fuel 2 fuel pump was weak and little screen at in was partially clogged. Little filter in fuel regulator was glogged so just replaced entire fuel regulator. When i did all that i disconected all the fuel lines and blew out. Make sure if you blow into fuel pump line to water seperator you first remove water seperator filter or ya end up with a mouth full of gas ( ask how i know that) when i did that a bunch of rust and crap blew out. Then after all that i filled new filter with 75% sea foam and 25% gas and ran at 2000 rpm for 5 minutes. Motors run great now
 
Just a fyi. And important for this problem. When you take off water seperators dump old gas in a clear glass jar. Let sit and inspect. This will give you a good guideline on what your fuel, fuel lines, injectors and tank look like. I have no just resolved myself to a monthly water seperator change. That shockingly is our only fuel filters on these boats. Worth the $25 a month cost for piece of mind
 
Thanks, I’m going to check compression on that motor just as a baseline but I suspect some kind of fuel issue. If I’m lucky it’s the canister but I doubt it. The motor runs fine, gets on plane and cruises great, etc. I think I’m just down a little power
 
At 20 years old, all your fuel lines should be replaced, they deteriorate from the inside out. There is also a ferrous fitting in the filter housing that rusts and sends flakes downstream to the pump.
 
this may need to be said as a reminder as something to check....the fuel/water separators are available in different micron sizes that allow for more or less filtering of the fuel as it flows through the separator.....if you use the wrong (smaller) micron filter element it can and will restrict the fuel flow thus possibly affecting engine performance at higher rpm's by starving the engine for fuel....

cliff
 
Cliff you are right. I only use a 10 micro filter and would not go any lower. Thats why i will just continue to check and change monthy
 
Cliff you are right. I only use a 10 micro filter and would not go any lower. Thats why i will just continue to check and change monthy

Taking the port side cooler assembly looks to be nearly impossible. Did you unbolt it from the block first then drop it down?

I’d like to blow all the lines out and probably start with the regulator as well but I know how tight it is down there
 
Dont need to. Just take 2 bolts off plate. Pull entire unit about an inch. Pull Pump front from cooler. Will just drop down and your pump is free to change and blow lines. I used a roll of electric tape to put between cooler and bracket to get to regulator. No need to remove water lines. Just a fyi. It did help to remove belt and just drop down alternator. No need to remove just drop down. Hope this helps.
 
Awesome thanks. The flow diagram is a little confusing but I’m sure it’ll be clear once I get it apart. It looks like:

tank->fuel filter->regulator->filter->pump->rail

Of course I could start by testing fuel pressure but I dumped my fuel filter and it had a fine layer of rust so my guess is the lines are shitted up
 
Screenshot_20190522-203521_Chrome.jpg
 
Yeah that’s what I’m using. This is a royal pain. So you took off the two #28 nuts so it drops?

Did you order any seals or gaskets as part of the pump and regulator? I don’t want to get I think apart and find I’m missing stuff
 
The reg comes with the small hat looking screen and there is no gaskets or o rings needed. Bottom of reg has a o ring installed. Pump comes with the main fitting and o ring. If you want can order 4 little o rings for elbow on front but no need to. Mine was fine
 
The reg comes with the small hat looking screen and there is no gaskets or o rings needed. Bottom of reg has a o ring installed. Pump comes with the main fitting and o ring. If you want can order 4 little o rings for elbow on front but no need to. Mine was fine

Thanks Jeff, last question. Looks like the Oring side just pulls out of the elbow, is that what you found?
 
Yes. No bolts no nothing. The o rings keep it in to elbow. When you re install plate the keeps it from moving
 

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