Hard cold starting 260

[rev.ronnie]

Hi all,

I have a 2.5 EFI 260 horn engine that really starts hard when it's cold. It cranks, will pop now and again, cranks a bunch more, pop, fart and finally start and then idle normally. Fuel pressure is 45#. both filters are new, as are plugs, wires and coils.

I just had the injectors serviced by Brucato, it runs like a dream in every other way. I have tried cracking the throttle slightly' which sometimes helps. I have a Brucato ACU.

I am seriously considering plumbing in a nitrous purge solenoid and a Hilborn button injector in the front section to use as a primer system.

Would the Steam Wheel be a good cure instead? Could you just crank it full rich to start it?

My key switch does crank the motor when you push it in from the on position. This would normally be a choke solenoid switch on a carb setup, but is it an enrichener for starting and just not working with the ACU?

Is there some starting procedure I'm missing?



Thanks in advance, Ron

[perfmarine1]

Sounds lean,check with Brucato how there acu enrich for start,factory ecu can be hooked up 2 ways auto enrich or push key to enrich.I like the later. Had a customer with a 260 with same prob,very hard start,but seemed to idle and run ok. All his intake cases were warped. So I would lap all intake cases,it is not hard to do.This worked for me his motor fires right up now. My 2 cents.

[rev.ronnie]

Thanks, I thought there may be some sort of factory enricher but I don't know if the Brucato unit has it. It actually seemed to fire better cold before I had the injectors done and ACU re-flashed. This was because the injectors wer grossly fat and flooding though.

I'll call Brucato tomorrow.

[mirage243]

Buy a Brucato steam wheel, turn dial 30% rich and spin motor over till it pops, turn dial to 10% rich and it'll fire right up. Guaranteed. They are the best starting device for these types of motors, PERIOD>

[Jay Smith]

Some of the 260's seem hard to start on some engines because the operator wants to open the butterfly prematurely or pump the throttle like a car. WON'T WORK !!! When cold I turn the fuel pump on and let the fuel cycle at least 30 seconds through the fuel system before I hit the key. I do this with a completely closed butterfly.I let the motor start and run with the butterfly closed for at least 10-15 seconds then they will normally accept fuel delivery and act normal...

my .02
Jay

[Dave Strong]

Follow the yel/red wire from the ECU harness, it normally goes to starter soliniod. If it is hooked to the yel/blk wire on the 9 pin harness, someone has changed it so you must push the key in while cranking to get cold enrichment. Many were changed to help with poor hot starting.

Dave

[Jay Smith]

His ECU is an ACU Dave.

Jay

[Dave Strong]

DUH, missed that reading to fast or something.


Dave

[rev.ronnie]

It sounds like the Steam wheel is the way to go with the ACU. It is a direct plug in to the male plug in the inside of the box, or do I need to send it back and get a retrofit?

[mirage243]

It sounds like the Steam wheel is the way to go with the ACU. It is a direct plug in to the male plug in the inside of the box, or do I need to send it back and get a retrofit?

Plug and play, no need to send it back to Brucato

[Jay Smith]

Some of the earlier ACU did not come with the pigtail to attach the dash board Steam Wheel. If yours was one of the earlier ones or one that the buyer didn't request that pig tail when ordering it will have to be sent back for retrofit.

My folks love the steam wheel...

Jay

[Tony Brucato]

Thanks, I thought there may be some sort of factory enricher but I don't know if the Brucato unit has it. It actually seemed to fire better cold before I had the injectors done and ACU re-flashed. This was because the injectors wer grossly fat and flooding though.

I'll call Brucato tomorrow.

Ronnie, the ACU has an enricher, but it works differently than Mercury's. With the Mercury box you can push the enricher in and buzz the injectors without turning the motor over. With the ACU, the injectors won't buzz while the motor is not cranking or running. With the ACU you must push in the enricher WHILE cranking to increase pulse width by 2 MS.
You can also hook up your Yellow/red enrichment wire to the solenoid and have it enrich everytime.

Ohm test your air temp sensor also. The ACU uses the air temp sensor for it's own cold start routine.

Call me if you need any help.

Tony

[Steve Pope]

Does that apply to the PCU also? Steve

[rev.ronnie]

Ronnie, the ACU has an enricher, but it works differently than Mercury's. With the Mercury box you can push the enricher in and buzz the injectors without turning the motor over. With the ACU, the injectors won't buzz while the motor is not cranking or running. With the ACU you must push in the enricher WHILE cranking to increase pulse width by 2 MS.
You can also hook up your Yellow/red enrichment wire to the solenoid and have it enrich everytime.

Ohm test your air temp sensor also. The ACU uses the air temp sensor for it's own cold start routine.

Call me if you need any help.

Tony

Tony, thanks for the info. My key switch actually cranks the motor when you push it in. I'm thinking that that's so you don't have to push and turn..

Is the red/yellow wire in the ACU pigtail? Also, what should the value of the air temp sensor be?

I don't think I want it to enrich all the time. It starts flawlessly when warm, in gear, with the bump of the key, especially now that you folks squared away the injectors!

Thanks, Ron

[rev.ronnie]

I looked into my wiring a little harder and found something. Both the enrichment and starting wires from the key, were going to the solenoid. The yellow/red wire going into the ACU harness was not hooked up at all. I hooked it up to the enricher wire from the key switch and now all should be well.


I'll try to fire it again today and see!

Thanks, Ron

[Tony Brucato]

Does that apply to the PCU also? Steve

Same with the PCU.

[Tony Brucato]

I looked into my wiring a little harder and found something. Both the enrichment and starting wires from the key, were going to the solenoid. The yellow/red wire going into the ACU harness was not hooked up at all. I hooked it up to the enricher wire from the key switch and now all should be well.


I'll try to fire it again today and see!

Thanks, Ron

Yes, you should have the Yellow/ black from keyswitch harness and Yellow/red from ECU harness to be connected for keyswitch enrichment.

[rev.ronnie]

Yes, you should have the Yellow/ black from keyswitch harness and Yellow/red from ECU harness to be connected for keyswitch enrichment.

Tony,
Ok, that makes sense. The yellow/black was the enricher circuit, and yellow/red starter circuit on the key switch. I thought they were backwards so I rewired them so the yellow/red is the enricher...well, same function anyway.

Thanks, Ron

[rev.ronnie]

Fired it up today. Booyah!! She cranks a little and pops off great!

Thanks Tony, helpful as always!

Ron