exhaust temp

[sterling]

Gone out today with the bernico 26 catamaran,2x2,5 EFI 260,s year 96
one engine has the analog style ECU,the other a digital one ending at A5,that I bought new a month ago, due the throttle position indicator was faulty,and midas says NLA,I bought a digital one .
The dealer set it at 101 % and I tried several runs ,but it was to rich (we thought)
because :It was slower on acceleration than the analog one,in the exhaust I saw that the one with the digital ecu was all black,the analog not.
So we hooked up EGT,s on both engines,2 probes on each engine.
at 101% we had 1320 F,at 99% also around 1300+F,at 103 %we had again 1300+F
this was driving us crazy,so we went home and found that the engine with the digital unit was having 23 degrees BTDC.
Could this be our high gas temp?Our HP dealer says normally they all run around 100% on stock 260,s.
bye the way the other 260 (analog one )had 1220F full trottle ,but has a lean hot spot at 1300F+in midrange.A27 I believe(do not sure)
At first we thougt that it was so rich that it was throwing flame,s ,but at 99%????
fuel press is 37-38 psi.
I,m going to set the timing at 25 degrees,and try it again next weekend at 103 %
just to see what happens.
I know 4 strokes are running high EGT,s when the timing is too late.
Dunno if a 2 stroke is doing the same?

Pan Ronnie was in the boat while measuring EGT,s and since he ,s having a bad karma, I am very lucky that one of my engine,s didn,t blow up.
Normally every engine that comes close to him blows up sooner or later.
But I was glad I could use his EGT,s and merc tools.

Anybody?

[slikcraft]

Sterling buy two 250 XS and your problem is gone.

[sterling]

Sterling buy two 250 XS and your problem is gone.

Slikcraft,thanks for this answer,it was the answer I was waiting for.
Now if I only could use your bankaccount ,than all my problems are gone.

Thanks for help

Sterling

[150aintenuff]

sumthin sounds fishy... pyro over 1100 is generally aproachingto hot.. 1200 VERGING KABOOM.. 1300+ BIG BANG...... are you sure you wernt reading flames easiest way to correct ecm issues is to go with a PCU from brucatto.. do both engines and then get steem wheels for both and set them on the go....

[PanRonnie]

you should atleast post a picture so everybody can see wat you are talking about :cool:
and for godsakes wear some glasses nex time so you can spot those big red iron boei's a little sooner before i can touch them with my hand :eek:

[eyeloveboats]

I have 2 260s 1 is a96 1 is 98 if it all fails go back to basics the different ecu might have different fuel curves and the moters are working aginst each other ps. use egt for a guide dont trust the numbers mine reads1350 at 103% good luck

[1BadAction]

sumthin sounds fishy... pyro over 1100 is generally aproachingto hot.. 1200 VERGING KABOOM.. 1300+ BIG BANG.....

Why do you post on something you know nothing about? You must have zero experience with pyros, because 5 minutes using OB pyros and you would realize they are the most in-accurate gauge from setup to setup. depending on probe depth you can make it read 200 degrees high or low. not to mention hes going to run into the same problems with a PCU, with even MORE adjustments to get him screwed up. Nick your a nice guy and I think you mean well but damn man.
.
.
.
.
.


Sterling, Tune your motor by reading the plugs. there is plenty of info about it on S&F. once you get the correct amount of fuel to the motor, put the pyro on it and get a reading. If your gauge reads (for example) 1350° then that is your base line. keep an eye on it and if it goes hotter (in different conditions) you may need to richen it up a bit. A pyro is a good tool to monitor an engine, but its not worth anything unless you know what it is supposed to read when the engine is running correctly.

[sterling]

Thanks for the info guys ,I haven,t tried again since last time ,the weather went bad ,and still is ,its winter overhere.
I,m going to set the timing at 25 degrees first.
Than I,m going to make a test run and look at the sparkplugs and the top of the piston.
Also I will put the pyro,s back.
Does anyone has experience with gaffrig pyro,s? and how they will hold up if I run them all the time in both engines?
The pyro,s I used are from a friend,their from mercury(thin ones)
They stick about 1/2 -3/4 inch in the ports is that properly mount?

How are you guys set timing?A HP dealer here put 6 timing marks on the flywheel,and make 5 new points,and timed all 6 just to see whats going on.
And usually he timed at no 5.
Is that a good idea?

Regards sterling