Compression testing a Ficht

[fichtfart]

Need to / want to do a compression test and am getting too much arm chair opinions. Got a 99 Ficht 150, no problems really- but will be decarbing, and changing plugs- so why not see whats it at? All advice has been from non boat owners- so what better place to ask....<br />Gotta do it in the driveway- manual says all 6 plugs out- and gage. Some have told me to do it at WOT, I'm assuning via in WOT idle, does it have to be WOT idle. Can you push it to WOT and turn it over? Is this correct? Or couldent you just pull the 6 wires off, and do cylinder at a time, putting in the new plug when that cylinder is done? Or would that build up too much pressure in the 'plugged' cylinders, and be hard to crank.<br />Most I've tested were single plug lawnmowers.

 

[Hooty]

Re: Compression testing a Ficht

Remove all the plugs and spin engine with ignition switch "off". You can do this by jumping the starter solenoid. It doesn't matter where the throttle is, just so it's the same place fore all 6 cylinders.Spin engine until gauge reaches its maximum reading for each cylinder. The only thing you're doing is comparing one cylinder to the next.<br />When you replace the plugs, they have to be indexed. If you don't know how to do this, better get a shop manual.<br /><br />c/6<br /><br />Hooty

 

[fichtfart]

Re: Compression testing a Ficht

I assume you mean the indexing of the gap to the injector within 90deg, with a torque of ~18flbs? I'm aware of it, but I have not found it in my Service manual yet. Is it possiable the manual I have p/n 520211, is pre update?

 

[Hooty]

Re: Compression testing a Ficht

I don' know. If you have a OEM manual and it doesn't address plug indexing, I'd check with friendly 'rude wrench.<br /><br />c/6<br /><br />Hooty