Crescent 45 (Archimede Volvo Penta ) help required

[JackMa]

Hello everyone,
I'm new to this forum and also to boating and outboards, so I hope being here will help me to get up to speed with the basics.
I just bought a second hand Crescent 45 outboard 3 cilynders. Through some internet research I have done, I believe these engines are also known as Archimende Volvo Penta.
It's got good good compression on all 3 cylinders. I have checked this with a compression tester.
However, it doesn't seem to have any sparks on the spark plugs.
I have tried to change the one of the plug, moving it between the coil leads, but still nothing.
I presume there is something wrong with the stator / trigger or with the DCI pack.
See photos of the engine attached.
Can someone help me to understand what I need to do to understand what the issue is?
Does anybody have a service manual that could help me to throubleshoot the issues?
Many thanks in advance.
Jack

 

[VicS]

Check that the operation of the stop button and that there is no short in the wiring.

You mention CDI pack but are you sure it has CDI , not points ignition. Points are likely on something this old and I dont see a CDI pack in any of the photos

 

[rotrax]

Kim Newcombe used such an engine in a motorbike for GP Racing. His had points, and it was a tricky job to get them right.

 

[JackMa]

Thanks for your replies.
I will check the stop button and its wiring.
Probably, you guys are correct in saying that it may have points. I just naively assumed it was a CDI pack. It's just a confirmation of the learning I have to do on marine outboards

 

[neil_s]

welcome JackMa! I'm also a Crescent owner, but mine is only a 3.9!

 

[JackMa]

welcome JackMa! I'm also a Crescent owner, but mine is only a 3.9!

Thanks. Do you know where I can find a service / owner manual for these old Crescent outboards?

 

[neil_s]

Thanks. Do you know where I can find a service / owner manual for these old Crescent outboards?

Sorry - I learnt about mine by taking it apart. Well, in truth, it fell apart through corrosion in it's leg and in the main bearings. I ended up with a working motor again by combining the best bits of two other non-runner engines. Sadly, it doesn't run quite as well as it did originally and I can't discover why. Some parts come up on e-bay every now and then, but this is getting less frequent .

 

[JackMa]

Hi, some updates on my attempt to get this outboard running again. I have cleaned all connectors and breaker points and I have managed to get sparks on all spark plugs!!
I now need the flywheel nut, since the thread of the original one is ruined.
I bought a M14x1.5mm nut, but it doesn't fit. I presume it's a M14 fine pitch, so M14x 1.25mm.
Can somebody confirm if this is the right thread for the nut or if it's an imperial one?
Thanks in advance.

 

[rotrax]

Hi, some updates on my attempt to get this outboard running again. I have cleaned all connectors and breaker points and I have managed to get sparks on all spark plugs!!
I now need the flywheel nut, since the thread of the original one is ruined.
I bought a M14x1.5mm nut, but it doesn't fit. I presume it's a M14 fine pitch, so M14x 1.25mm.
Can somebody confirm if this is the right thread for the nut or if it's an imperial one?
Thanks in advance.

Not without seeing it I'm afraid.

Might pay you to get a set of thread gauges or, if you dont have one, a good vernier caliper which might help accurate measurement of the number of threads per inch.

Google will give good info on what thread it might be once you know basic dimensions.

Well done so far, keep it up!

 

[JackMa]

Hi All,
sorry for the radio silence but it took me a while to get to this point.
The good news is that the motor is now running!!
The flywheel nut was a M14X1.5mm in the end. The first one I bought wasn't M14X1.5mm, the seller sent me the wrong size.
Now I have another problem. I have no water flowing out from the exhaust relief, but only from the rubber hose that connects the bottom of the exhaust cover to the copper pipe that goes all the way down to the water pump (see photos attached for reference).
I have been told that for this motor water should only come out from the exhaust relief and not from the rubber hose on the side.
I was wondering if anybody can confirm this.
I have disassembled the exhaust cover to check its condition and it seem fine, I can't see any signs of blockage (see photos attached for reference).
I hope somebody can provide some guidance on this matter.

Thanks in advance.
Jack

 

[neil_s]

Well done! It does look like that hole in the rubber pipe is intended to be there. The squirt from it confirms your water pump is OK. What you really want to know is :- ~Is water coming out of the exhaust at the bottom of the leg?" One thing that comes to mind - does the motor have a thermostat? You might need to dismount the power head from the leg to see what's going on there.

 

[Boater Sam]

Have you tried looking for a manual on line?

Try Volvo outboard engines technical manuals

 

[JackMa]

Thanks All for the info.

@neil_s, that's exactly my issue, water doesn't flow out from the exhaust relief at the bottom. The motor has a thermostat also shown in the photo of the exhaust cover previously shared. My question is: Does the thermostat need to be open for the water to come out from the exhaust relief? Thanks. Jack

 

[JackMa]

Afternoon All,
I have some good news: water now comes out from the exhaust relief!! (see photo attached)
I have removed the thermostat and run the engine without it and it worked fine.
Then I have tested the thermostat by submerging it in some hot water and it also works fine.
In summary, when the motor is cold only spits water from the rubber hose at its side. By keeping the engine running for a while, when it reaches a certain temperature the thermostat opens and water starts coming through the exhaust relief, as well as the rubber hose.

One more thing I noticed is that lifting the motor up and turning it left and right is very hard. Feels really tight and stiff. I tried to untighten the bolts at each side of the outboard (see photo for reference) but it didn't make any difference. Any suggestions?

Thanks.
Jack

 

[Boater Sam]

Giggle pin needs removing and greasing.

 

[JackMa]

Giggle pin needs removing and greasing.

Thanks for the info