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JustMercMe
01-20-2009, 02:58 PM
1st thing....I'm new to the whole big block thing being that I've been into these drag outboards for so long but am willing to learn and somewhat mechanically inclined.....Just haven't done a whole lot on car motors! :)

#1. Boat has been sitting for around a year now and has around 8 gals. of old gass in it. I put 10 gals of 93 oct. in with some booster and fired it up and started missing a lil on one side. Should I drain all fuel and start fresh?or just add some seafoam and fuel injection cleaner and run all the fuel out?

#2. Before she sat for a year I was having some water pressure issues and the buzzer was going off. Kinda wierd b/c It would be normal on a run then you stop, fire it up again and the pressure would be low....Would'nt it be a steady lower pressure for a water pump problem? Soundsto me kinda like a floating blockage somewhere? Where do I start looking?


Thanks ahead guys....

donzi2287
01-20-2009, 05:54 PM
Get rid of the fuel...You are going to scratch your head for several tanks. Also, have you changed your impeller? Sitting for a year is not good for them and they say every year anyway...I'm Koo Koo and do it every 6 months!!!

BigGrizzly
01-21-2009, 10:44 AM
Merc What happens is bad fuel does not get better with stabilizer it gets worse. Get rid of the fuel- all of it. replace the plugs and wires and start fresh.

fasttrucker
01-21-2009, 01:33 PM
Change the fuel filter and the impeller.A new impeller is a lot cheaper then new head gaskets and motor damage.

JustMercMe
01-21-2009, 04:50 PM
Thanks guys!....Rigging up an old Holley pump for removal tonight.....Gonna try and cruise a lil this weekend. Going to get a filter and impeller tomorrow.

Is there a (easy)way to backflush the raw water cooling system?

MOP
01-21-2009, 06:32 PM
You can get some of the junk out by disconnecting the circ pump hose and removing the block drains then feed water into the garden hose. That will give you a fair bit of water flow but no real pressure as it will dump out of the risers unless you block the hoses that feed the risers. You will not get a heck of a lot out but it is better then nothing. Do it before you redo the pump, then back flush the oil cooler using the hose tha feeds from the pump where it meets the block that should blow and impeller shards out.