I have a 1975 Mercury 1150 (distributor) that was running great. I was away from lake for about 2 weeks and upon return I find the motor bogs down and won't make over 2000 RPM even though it starts and idles great and will run along all day below 2000 RPM.
The carbs were cleaned back in July and I also did a full lync and sync at that time. Compression was great and even across all cylinders then as well. Fuel is new and bulb stays hard under acceleration. I put in new spark plugs and am getting spark to all plugs at idle.
What should I be thinking? When I shut her down two weeks ago all was great, now this. Can a powerpack be the problem and can that "just go" while sitting?
Please let me know what/how I can check next?