I have a 26' V hull Home build boat with a Volvo AQ131D engine
Took it out was running what appeared to be fine but i May have multiple issues. The Tension Arm bracket went underway and overheated the engine. Blowing the seal on the Heat exchanger
I Took the exchanger back and refurbished it Dropped it back in the boat and didn't see any evidence of a blown head gasket. Brang it back but it would not come up to any decent RPM and had to drive it home around 2k RPM.
When I started troubleshooting at the dock I did a compression test to maybe rule out the head gasket and it reads 185-190 across all 4.
Plugs look good
Dwell was out about 10 degrees out so adjusted and timed it. (electronic ignition on order)
Timing is rock solid at 6 Degrees BTDC at idle and at 4200 RPM it is bouncing between 32 and 36. (spec says 32-36)
Sounds pretty good dockside maybe a little off at 4500 or so.
Take it out in gear WOT tops out at about 3500 and boat is up on a plane. (should i be getting the full 5k if i want it?)
Runs good for a half hour but is warming up to around 210 on the dial (checked with IR thermometer multiple places and cant find anything hotter than 190) (spare exaust manifold being blasted and rebuilt)
At the half hour mark i back the throttle down and cool it back down to 190 on the dial try and reaccellerate and it bogs down.
When i drop it out of gear and it accelerates smoothly
Have to return home yet again at about 2k
Back dockside under no load It was still good on timing / dwell but did sound worse off than cold/ normal operating temp when first going
Any thoughts?
Took it out was running what appeared to be fine but i May have multiple issues. The Tension Arm bracket went underway and overheated the engine. Blowing the seal on the Heat exchanger
I Took the exchanger back and refurbished it Dropped it back in the boat and didn't see any evidence of a blown head gasket. Brang it back but it would not come up to any decent RPM and had to drive it home around 2k RPM.
When I started troubleshooting at the dock I did a compression test to maybe rule out the head gasket and it reads 185-190 across all 4.
Plugs look good
Dwell was out about 10 degrees out so adjusted and timed it. (electronic ignition on order)
Timing is rock solid at 6 Degrees BTDC at idle and at 4200 RPM it is bouncing between 32 and 36. (spec says 32-36)
Sounds pretty good dockside maybe a little off at 4500 or so.
Take it out in gear WOT tops out at about 3500 and boat is up on a plane. (should i be getting the full 5k if i want it?)
Runs good for a half hour but is warming up to around 210 on the dial (checked with IR thermometer multiple places and cant find anything hotter than 190) (spare exaust manifold being blasted and rebuilt)
At the half hour mark i back the throttle down and cool it back down to 190 on the dial try and reaccellerate and it bogs down.
When i drop it out of gear and it accelerates smoothly
Have to return home yet again at about 2k
Back dockside under no load It was still good on timing / dwell but did sound worse off than cold/ normal operating temp when first going
Any thoughts?
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