Replacing A VP AQ125A Distributor ???

[ibizian]

I am looking for a distro replacement for dummies. I am replacing the distro and coil to electronic and I know sure as shooting that as soon as I pull it off I will realize there was something that had to be lined up with something else and I went and screwed it all up.

Anyone got a manual to keep me from screwing it up??? Possibly with Pictures??

Let me know so I can get it fixed and on the water one last time!!

Thanks for all who hlep the less knowledgeable by sharing all the mistakes you have made or seen before!

 

[captmello]

Re: Replacing A VP AQ125A Distributor ???

I've never replaced a distributor on your motor. However I can give you an idea of issues that could come up.

1. Mixing up the plug wires.
2. installing the distributor wrong.
3. timing the engine incorrectly.
4. rewiring the distributer incorrectly

What your doing is pretty easy. Here's how I R&R my distributor when I replace my points in the spring.

turn the engine to TDC timing mark. Check the rotor the make sure it is pointing a #1 cylinder spark plug wire on in the cap or just before it. If not your one more crank around of the engine to TDC again.

Pull the cap off with all the wires attached so you dont loose track

Note where the rotor is pointing on the engine. When you install the new distributor, you want the rotor pointing the same direction as it was at removal.

Also, again note where the #1 spark plug wire is in relation to the rotor, as you want the rotor pointing toward that spark plug wire pickup in the new cap when you install it.

Thats about it for the Distributer. Once you get it put together this way, hopefully it will start and run well enough to set the timing with a strobe.

Coils got two posts - and + get the wires back on the correct posts.

Label all your wires if need to, or switch them directly to the new coil.

Read any instructions that come with your new parts. You may need to remove the ballast resister. However I don't know if and where yours would be. Mine is mounted right next to the distrib.

Good Luck.

What kind of distributor/coil did you pickup?

 

[ibizian]

Re: Replacing A VP AQ125A Distributor ???

What kind of distributor/coil did you pickup?

I got the entire kit form these guys. http://www.hot-spark.com/
Good price and fast email response as well. Very good to work with.

I am not sure when I am actually going to tackle this project as we had a snap freeze before I got the water drained so that is first on my list of things to do!!

 

[mcleaves]

Re: Replacing A VP AQ125A Distributor ???

I did that conversion on my old 125A. You should not have to PULL the distributor to put the parts in. I DID end up lifting it out and moving it a couple teeth because the timing changed and I needed more headroom to turn it. You may not have to do that.

It was a great conversion (along with converting to dual carbs from one of the AQ series engines) , but can I ask why you are doing it? There is a reason I am curious...

 

[bruceb58]

Re: Replacing A VP AQ125A Distributor ???

Best thing to do is to pull the distributor while it is already at TDC and pointing at #1. As long as you put it back in the same place and you don't turn your engine, all you have to do is recheck timing after you are done.

 

[mcleaves]

Re: Replacing A VP AQ125A Distributor ???

Best thing to do is to pull the distributor while it is already at TDC and pointing at #1. As long as you put it back in the same place and you don't turn your engine, all you have to do is recheck timing after you are done.

Yup.. Learned the hard way on that one!

 

[ibizian]

Re: Replacing A VP AQ125A Distributor ???

I did that conversion on my old 125A. You should not have to PULL the distributor to put the parts in. I DID end up lifting it out and moving it a couple teeth because the timing changed and I needed more headroom to turn it. You may not have to do that.

It was a great conversion (along with converting to dual carbs from one of the AQ series engines) , but can I ask why you are doing it? There is a reason I am curious...

No I won't be that lucky as it is already installed in the NEW distro. I am replacing my distro with the new one with the kit installed. So find TDC and make sure it is pointing to #1 all at the same time. Sounds like a Rubicks cube of fun!!

 

[mcleaves]

Re: Replacing A VP AQ125A Distributor ???

No I won't be that lucky as it is already installed in the NEW distro. I am replacing my distro with the new one with the kit installed. So find TDC and make sure it is pointing to #1 all at the same time. Sounds like a Rubicks cube of fun!!

Hmm OK.. Not sure why you needed the whole distributor. The conversion kits screw in where the points used to screw in.

Anyhow, yes, find TDC and set it so the rotor points to #1, but it has to be TDC on the COMPRESSION stroke. Easiest thing to do is pull the plugs (your pulling one anyhow, make it easier byt removing the other 3) and turn then engine with a big socket while you have some paper towels pressed into the #1 plug. When it pops out you are on the compression stroke.

M

 

[ibizian]

Re: Replacing A VP AQ125A Distributor ???

Hmm OK.. Not sure why you needed the whole distributor. The conversion kits screw in where the points used to screw in.

M

Cost was a factor. I got the distro with kit installed and coil for roughly the cost of the kit alone so.... New distro, new coil, new electronic advance, it seemed to make sense to replace them all at once!!!!

I like your idea of TDC checking with the paper towels I will use that one. I assume there is a way to have it TDC and the distro not pointing to #1 so I will have to watch for that one as well.

 

[mcleaves]

Re: Replacing A VP AQ125A Distributor ???

Cost was a factor. I got the distro with kit installed and coil for roughly the cost of the kit alone so.... New distro, new coil, new electronic advance, it seemed to make sense to replace them all at once!!!!

I like your idea of TDC checking with the paper towels I will use that one. I assume there is a way to have it TDC and the distro not pointing to #1 so I will have to watch for that one as well.

Before you pull the dist, if you set the engine at TDC they way I suggested FIRST, you should just have to drop the new one back in pointing the #1 plug.

 

[captmello]

Re: Replacing A VP AQ125A Distributor ???

Someone please correct me if i'm wrong, but if it's not on the compression stroke wouldn't the rotor be pointing toward plug #3 (180 deg from #1?)

What about the ballast resistor? Did the Hot Spark people say anything about that?

 

[mcleaves]

Re: Replacing A VP AQ125A Distributor ???

It was always my understanding that the rotor can be on any give plug at 0 and 180. In one case it's on the compression stroke. In the other it's the exhaust stroke. I've always been told that having the rotor on #1 is not sufficient, that you could be 180 degrees out, ie on the exhaust stroke.

I know it takes two revolutions of the crank to get back to the compression stroke. I don't know if that is two revolutions of the dist though.

M

 

[mcleaves]

Re: Replacing A VP AQ125A Distributor ???

What about the ballast resistor? Did the Hot Spark people say anything about that?

When I converted mine it was not an issue. I only had the boat for two seasons after the conversion though so I don't know if affected the longevity of the ballast resistor

 

[captmello]

Re: Replacing A VP AQ125A Distributor ???

It was always my understanding that the rotor can be on any give plug at 0 and 180. In one case it's on the compression stroke. In the other it's the exhaust stroke. I've always been told that having the rotor on #1 is not sufficient, that you could be 180 degrees out, ie on the exhaust stroke.

I know it takes two revolutions of the crank to get back to the compression stroke. I don't know if that is two revolutions of the dist though.

M

Seems like a easy question to answer...

Anyone?

My boat is put away or I'd run out and, pull the dist. cap and crank it around.

 

[bruceb58]

Re: Replacing A VP AQ125A Distributor ???

The distributor does one revolution for every 2 revolutions of the crankshaft. Therefore, TDC can be either top of compression stroke for #1 cylinder or top of compression stroke for another cylinder depending on what motor you have.

 

[PiratePast40]

Re: Replacing A VP AQ125A Distributor ???

What about the ballast resistor? Did the Hot Spark people say anything about that?

I also have the Hot Spark kit and coil. The directions they supply specifically discuss coil and battery voltages and the use of a resistor wire. They stop short of telling you to eliminate or bypass the resistor wire or ballast except during testing.

Since I have their resistor coil, and the readings were in spec, I just removed the existing ballast resister from the circuit.

One thing no one has yet brought up - how does the "electronic advance" work for this scenario? I would think that it's a rather complicated affair and would involve more than just updating out the switch (points). I'm also pretty sure that the existing distributor would need to be upgraded. If that was just an error or mis communication, then it would be a good idea for the OP to go ahead and inspect and oil the advance springs and weights while the replacement distributor is out.

 

[captmello]

Re: Replacing A VP AQ125A Distributor ???

The distributor does one revolution for every 2 revolutions of the crankshaft. Therefore, TDC can be either top of compression stroke for #1 cylinder or top of compression stroke for another cylinder depending on what motor you have.

Thanks Bruce!!
So, with this cleared up, wouldn't the easiest way to find TDC for #1 cylinder on the compression stroke be to rotate the engine to the TDC make and check the distributor rotor? If it's pointing at #1 plug wire pickup than its on the compression stroke and if the rotor isn't pointing toward #1, rotate the engine one more time and it should line up with #1.

Seems easier than trying to rotate the motor while holding your thumb over the spark plug hole or some other trick.

I was mistaken earlier when I mentioned #3 being 180 Deg from #1, that would depend on the firing order of course.

 

[mcleaves]

Re: Replacing A VP AQ125A Distributor ???

Ahh I now see why you were digging at the question from the angle you were Capt. Yes, if you know where the #1 wires is and you and have not pulled the dist then you can just get the cyl to the top and look under your cap. But if you are putting a new one in you are going to need to make sure you are on the compression stroke. Yeah you can mark it and try to transfer the mark to the same spot on the new dist but there is too much room for error IMO

It's really not that hard to rotate the engine while checking the #1 cyl for pressure. Done it many times. Too many to be honest

And Bruce thx for clarifying where the dist would be on the exhaust stroke. I was incorrect saying it would be back on one. You are right it'll be somewhere, but not back on 1. The problem is that another cyl's exhaust stroke will be on #1 at some point

Bottom line is you need to get #1 cyl TDC and the dist rotor pointing at #1 plug. I guess there are a variety of ways to get there..

M

 

[bruceb58]

Re: Replacing A VP AQ125A Distributor ???

It is not really a problem locating it if the distributor is in and the engine has already been running. The problem occurs when the distributor gets pulled and the engine gets rotated. That is when you need to rotate to TDC and put your finger over the sparkplug hole to determine when the #1 cylinder is at the top of its compression stroke.

 

[Paul Ryan]

Re: Replacing A VP AQ125A Distributor ???

#1 TDC....On my AQ125A I open the oil fill cap. Look inside the valve cover toward #1 and can clearly see #1 intake cam lobe. Turning the engine clockwise (from the front) I watch the lobe until I see it open #1 intake valve
(lobe pointing straight down). Keep turning until the valve starts to close. The piston will now be coming up on the compresion stroke. Switching my sight from the cam lobe to the cam gear, conitinue to turn engine until the cam gear timing mark lines up to timing mark on valve cover. Done #1 TDC. If you look back inside the valve cover you can see both #1 cam lobe are off the lifters and pointing up (offest but up). Just fully rebuilt my engine. Used this process several times, worked great.