andysperformance

Boat is new to me 88 454MAG/Bravo one with 400 hours, took it out for the first time and after running around for a few minutes lifted the hatch to make sure all was OK, everything looked/sounded and ran fine except the risers/manifolds were too hot to keep your hand on, was told that they should be cool, temp on teh gauge never went above 140... SO I changed the thermostat with a new 140* disconnected all the water hoses to check for debris, all were clear, felt inside the oil cooler and again nothing.. when backflushing water flowed good same pressure in and out.. Took the manifolds and risers apart, all looked good. and water flowed through them fine when hooked direct to a hose. Installed new "open" gaskes and back to the lake.



Same thing, no change.. temps on gauge below ar at 140.. risers getting hot.. so next thing i could think of would be the raw water pump, took that apart today hoping to find my problem but to me looks good?

Orderd a new kit (with housing)for it today anyway. problem is they dont make the 2 pc housing anymore, will the 1 pc kit fit that i ordered?

What else should i check? checked the pump intake line from the drive also and it flowed freely..

FasterThanU87

take the impeller out of the housing an see if the fins stay bent if they do replace it also if the housing has ANY signs of wear inside replace as well

FasterThanU87

lol just now saw u ordered the kit but yea thats a common problem i've seen is the imp's go tits up

DMOORE

Well, all I can say is, after a long run in my ski boat(351 PCM) those manifolds are pretty damn hot. They cool down fast, but when running, they get quite hot to the touch. This is normal on every boat I've had that had cast manifolds. If ya start smelling burnt rubber, ten ya know ya have a problem..




Darrell.