Engine Power Loss

[Norman Downey]

Last fall I pulled by 77 Catalina 30 and stored it out of the water for the winter. I put the boat in the water last weekend and I am having trouble with the engine power. The problem is while in neutral the engine performs well, revs up with limited throatal movement; however, placing the the engine in gear, forward or reverse is much harder than I remember from last season and the engine bogs down when I give it power. Under normal operating throatal the boat will barely move. At times while being towed to the marina the engine would pickup and the boat would move normally until I take it out of gear and try to reengage the reversing gear, then the same problem would take place. I don't think it is the engine since while in neutral it runs perfect, I am thinking it has to do with the reversing gear, almost like something is binding and resisting the engine. Any thoughts????

[Mo]

Welcome aboard Norman,

If you had just launched ensure something didn't foul your prop...that could cause it.

This season I had a very similar problem. It did sputter a bit when I throttled up in neutral, however, it was on the verge of stalling when I put it in gear. I pulled the carb (it was clean), changed filters and still had the problem.

Then to ignition: Had fire to all plugs (plugs were new); figured I'd change points and condenser...still had the problem.

Finally, wanting to have a peek at the valves I decided to pull the plugs. Numbers 3 and 4 were wet with gas. I threw in a couple of old ones from my junk box and she ran perfect.

I put a new set of plugs in and all good....just goes to show you that sometimes even "new" plugs can fail.

My advise: check for fouled prop; check fire; check plugs...actually pull them and see if there is any gas on them. They will be dry if they are firing. You can also do the "hold the thumb over the plug hole for a quick compression check also. When the engine is turning over compression should pop your thumb up off the hole.

After that, check the carb for blockages. The main jet is a frequent spot for debris to cause fuel starvation. Might have to pull the carb and clean it up, change out filters....

My gut feeling is "fire" .... but make sure there is not something wrapped around the prop or shaft.

[Norman Downey]

Thanks Maurice, I did think about the prop being fouled; however, since i just put it in the water assumed all was clean. I will check in a couple of weeks when the water gets warmer. I still have a lot of top side work to do before we get out for our first sail. I will also checkout the spark plug issue. The plugs were new last year and don't have a lot of engine time so i assumed they are still in good condition.

[Dave Neptune]

Norman, I doubt that it is in the trans or reversing gear. If the trans was binding up a bit there should be a bit of associated noise when engaged~not the normal reverse whine. You have described a classic fuel starvation senario. I'd check the fuel preassure at the carb and if it is OK then I'd look inside the carb for a restriction, plugged passage or jet most likely. If the problem is in the ignition side it should be miss-firing.
Check the plugs if one or two look drastically different could be a plug issue although if they look somewhat normal or "the same" look to the carb or fuel delivery.

Dave Neptune

[JOHN COOKSON]

I want to bet two red chips on a stuck valve. Because the boat was stored for the winter this is high on my list of suspects. If there is a stuck valve it may free itself since the engine ran normally at times.

I would do a compression check first. If the compression is ok then go on to fuel, ignition and possibly exaust systems.

TRUE GRIT

[Jesse Delanoy]

I put in new spark plugs the beginning of each season. Thirteen bucks seems a cheap price to eliminate this source of problems.

[sastanley]

Norman, How did you winterize the engine last fall?

I am in agreement with John & Dave...fuel related or stuck valve (spring) are first & 2nd, bad plug is 3rd. Another way off possibility (you should have noticed this in the fall however) would be an exhaust restriction at the mixing tee above the muffler

I have a C-30 also, and can help out with most anything that may be specifically C-30 related..the only thing I haven't had (yet) is a broken valve spring (cross fingers!) or the need to remove the head. I've done just about everything else though!

On my engine, the #4 valves have been particularly pesky and like to stick..the solution here has been Marvel Mystery Oil squirted into the cylinders thru the plug holes after engine use and letting it soak in between weekends.

[Norman Downey]

Thanks everyone for the advice and information. I will go over the list this weekend and let you all know how things go. Shawn, my 1977 C 30's registration number i#345. I see where yours is #511. We have our a cottage on the Potomac River near Callao, Virgina and have sailed to the Solomans area.

[sastanley]

Norman, The northern neck of VA is roughly 1 Hour away by car. I still need to get my boat going this year (it is in pieces...not engine related), but I'd be happy to make a road trip to visit and try to help if needed...report back and we'll go from there.

[Norman Downey]

I checked the cylinder compression last wekend and have positive results. Cylinders 1 through 4 tested at 82 psi, 80 psi, 78 psi and 79 psi respectively. Spark plug tips were all white with the exception of cylinder 4 which had a little carbon color (more white than carbon). My next step is to pull the carburetor and check the bulb for varnish. After discussing my problem with several others on the dock it seems like the gas issue (ethanol additive) is the major issue.

[Will Jacocks]

I can agree with you on that, except that you may have been running too lean?