225 Excel hard to start when cold

**225XCL** · 01-13-2020, 05:30 PM

Hi Folks

I have a strange problem with a motor, it rebuilt it a few years back and its always been like it since then. It takes ages to fire when cold (first start of the day).
It fires immediately from that point on all day with out an issue, run hard with no problems.

The cold start is annoying me now and I'm trying to sort it out and to be honest once teh HPDI is up and running I will sell all of my Excel stuff and this motor needs to fire up quickly for a buyer.
I have put a new starter on as I didn't think it was spinning at 750rpm that it needs.
Battery is always charged prior to use.
replaced the relay in case there was voltage drop
The only think different on this engine to all my others is a set of boysen reeds. I'm considering swapping these with some CCMS reeds that where on another motor that is in bits atm.

Any other suggestions?

Cheers

**Markus** · 01-14-2020, 02:35 AM

An engine that is hard to start when cold is typically lean, so try bigger idle jets.

**225XCL** · 01-14-2020, 03:12 AM

Thanks for the post, that's interesting, the carbs are all factory jetting.
If I wind out the mixture screw that would help if that's the case wouldn't it?
Once its running it runs perfectly.

**Markus** · 01-14-2020, 04:16 AM

Try the pilot screws!

(But remember their starting settings)

Also, as far as I remember, the Excel had an electric primer circuit. (or was that the Special?).

I used one of those on an engine without choke, and it started like an EFI.

**LittleCharger** · 01-14-2020, 07:39 AM

I assume you are priming the fuel bulb to fill the carbs before cold starts

**Speedyy** · 01-14-2020, 10:27 AM

Make sure that all the choke plates are closing completely.

**225XCL** · 01-14-2020, 07:27 PM

Originally Posted by LittleCharger

I assume you are priming the fuel bulb to fill the carbs before cold starts

It has an electric fuel pump, i give it a good 2 min's to do that prior to starting.

**225XCL** · 01-14-2020, 07:28 PM

Originally Posted by Speedyy

Make sure that all the choke plates are closing completely.

That's definitely something to look at, cheers!

**Markus** · 01-15-2020, 08:24 AM

Originally Posted by 225XCL

It has an electric fuel pump, i give it a good 2 min's to do that prior to starting.

It should only take seconds to fill the float bowls.

In any case, a primer circuit from a Yamaha or OMC will work great with the electric fuel pump and make the engine really easy to start.

Finally, Yamahas start better when perfectly horizontal.__PRESENT

**BOATMANBLUES** · 01-15-2020, 08:43 AM

The draw holes in the choke plates on a lot of the Yamys is huge....too big to get a good draw when cranking....I found some snap in plugs at a hardware store that would pop in to the holes and block them off ...did bunches of them back when we were selling them motors new...much improved cold starts..

**225XCL** · 01-17-2020, 01:50 AM

I am loosing the plot, the manifold is the same cast as the 6R5 but its not plumped for the primer.
So back to the drawing board.
Reset all mixture screws from 3/4 to 1 1/2 turns out. We are getting some long over due rain atm so checking the choke will have to wait for a bit.
If these don't work I will try the carbs from a different powerhead that was having no issues starting and work from there, I'm still tempted to swap the reed plate out.

**LittleCharger** · 01-18-2020, 11:05 AM

Originally Posted by 225XCL

I am loosing the plot, the manifold is the same cast as the 6R5 but its not plumped for the primer.
So back to the drawing board.
Reset all mixture screws from 3/4 to 1 1/2 turns out. We are getting some long over due rain atm so checking the choke will have to wait for a bit.
If these don't work I will try the carbs from a different powerhead that was having no issues starting and work from there, I'm still tempted to swap the reed plate out.

Drill and plumb the intake for a primer, that’s all I did, epoxied in some 2.5mm brass tubes for the primer fuel lines