Replacement shift interrupter system help needed

[Southeast Cruiser]

The shift interrupter is bad on my boat. It is a rectanguler prism shaped piece located in-line at the throttle/shifter assembly. The original p/n is 3857604. VP no longer has them. I am looking to replace the system to something that is available now. Can I adapt a mercruiser shift plate assembly or something else simpler to it since it basically started as a mercruiser block before going to Volvo Penta? Whatever I need to replace is fine...throttle/shift assembly, etc.

The boat is a 1994 Crownline that came with an 8.2L but now has a 2002 8.1 GXI-AF (s/n:4012071102) The ECM is a MEFI 4. The J1-20 pinout is the shift interrupter connection to shut down (ground) the coils to lower the RPMs to allow it to come out of gear while moving. The blades stop instantly on the trailer of course but in the water she won't come out of gear.

Thank you in advance for the help...

Scott

 

[Southeast Cruiser]

Re: Replacement shift interrupter system help needed

I was also told that possibly lowering the in-gear idle RPMs may fix it. I have the Diacom software so I am able to look at the setting ( Current "desired" setting is 663 rpms) Is this something that can be hooked up to a computer at a VP shop and be manually adjusted via a couple keystrokes or is there more involved?

Thanks again for any help,

Scott

 

[Don S]

Re: Replacement shift interrupter system help needed

Volvo's don't use the shift interrupt systems. If it's not coming out of gear you have either a cable problem, or a drive problem. What outdrive do you have? Need numbers or pictures, don't just say Cobra, that would cover 3 completely different drives.

 

[Southeast Cruiser]

Re: Replacement shift interrupter system help needed

I certainly won't argue your knowledge, but the fact that it had one on it and it was wired up led me to believe it used it. The part has an official Volvo Penta part number sticker on it and it reads Shift Interrupter right on it. And it comes out of gear easily and instantly on the trailer from forward and reverse.

The shifter cable was replaced and no difference.

The outdrive is a DPX. See pics below...thank you

 

[boatguya1]

Re: Replacement shift interrupter system help needed

That is your remote. It does not have a shift interupt switch it has a neutral safety switch. The neutral safety switch does not effect coming out of gear.

James

 

[Don S]

Re: Replacement shift interrupter system help needed

Do you know what the original engine and drive model numbers were?
When Volvo first went into the joint venture with OMC in 94, Volvo did put the shift interrupt connection in the harness and to the ECM's so they could be used with the older Cobra style drives with dog clutches, which did require the shift interrupt switch.
You have a DPX drive in your pictures, and it has a cone clutch and does not require a shift interrupt switch.

 

[Southeast Cruiser]

Re: Replacement shift interrupter system help needed

Don,

I was looking through the previous owner's paperwork. I have no record of what was first in it but I believe he said it was the 8.2 liter engine that originally came with the boat (1994). The outdrive is the original one to the boat (DPX-1994). I think the serial number for the DPX is 3102149509. I had that written down so I must have read it off sometime. Only the engine was replaced. I have the paperwork stating so. He also gave me the stern drive shop manual he had (Volvo Penta 1994-1996) Both the 8.2 and the DPX are in it.

Looking through more of the service records I noticed that one mentioned the removal of the remote control, installation of a shift interrupter switch, reassemble remote. So it sounds like it did not originally come with one, just like you said. It mentioned "hard shifting" and the fix was to disassemble head unit, remove & replace clutch cone, reassemble & install on drive, then pressure tested for leaks.

Scott

 

[boatguya1]

Re: Replacement shift interrupter system help needed

My appologies, I've been doing this full time for 20 years and have never seen this before. Try marine parts express looks like they may have it. You won't like the price.

Don, did you look at his photo closely? It looks to be mounted on the shift cable at the remote and is an interupt switch.

James

 

[Don S]

Re: Replacement shift interrupter system help needed

Don, did you look at his photo closely?

Did you read the last paragraph of his last reply?

The upper gear box also has an adjustment for the shift mechanism, and I would guess that after the shift cone was replaced the shift mechanism was not re-shimmed or it was done improperly.

Here is some info from the DP-E manual, you won't have the special tool, but you can still turn the shift lever to the proper position by eye to check the shimming. For your DPX, you only want to go one shim, not 3 like the DP-E, Those were for diesel outdrives. For gas, use one shim.



Click the image 2 and even 3 times to see it larger.

 

[boatguya1]

Re: Replacement shift interrupter system help needed

Did you read the last paragraph of his last reply?

The upper gear box also has an adjustment for the shift mechanism, and I would guess that after the shift cone was replaced the shift mechanism was not re-shimmed or it was done improperly.

Here is some info from the DP-E manual, you won't have the special tool, but you can still turn the shift lever to the proper position by eye to check the shimming. For your DPX, you only want to go one shim, not 3 like the DP-E, Those were for diesel outdrives. For gas, use one shim.

View attachment 137625

Click the image 2 and even 3 times to see it larger.

Reading your post with the quote it appears that may have come accross poorly. I asked if you looked at the photo closely as I did not the first time I looked and missed the interupt switch on the cable. As I said I have never seen one and found it interesting.


James

 

[Southeast Cruiser]

Re: Replacement shift interrupter system help needed

Don,

I will see what I can do about the shim check. Thanks again. I will let you know.

James,

Thanks for the info.

 

[Southeast Cruiser]

Re: Replacement shift interrupter system help needed

Here is some info from the DP-E manual, you won't have the special tool, but you can still turn the shift lever to the proper position by eye to check the shimming. For your DPX, you only want to go one shim, not 3 like the DP-E, Those were for diesel outdrives. For gas, use one shim.

Don, I ordered then purchased the special tool. It's a p/n: 3856761-8. Reading the instructions, I quote..."DPX-S1, DP-D2, SX-C2, DP-S1, and SX-RT2 Only: ...install 3 additional shims to the shim retaining screw." Don't I have the DPX-S1? Or does the "S1" mean diesel?

Scott

 

[bruceb58]

Re: Replacement shift interrupter system help needed

deleted

 

[Don S]

Re: Replacement shift interrupter system help needed

I don't know if you have the DPX-S1 or not. You have to look at the tag on the upper gear box and see what it says.

 

[Tazmann701]

Re: Replacement shift interrupter system help needed

Any update? Having the same problem and I'm hoping you found the fix. Thank you.

 

[Don S]

Re: Replacement shift interrupter system help needed

If you have a problem, might want to start your own thread, what fixes his, may not fix yours. Besides, he hasn't been back to the forum since his last post.