engine coupler help

[yfzjim]

So I have my engine out and Im waiting on my replacement from Rapido. It has been suggested to replace my coupler while its out. I didnt realize something so simple would be so expensive. Do I really need it? Can I tell by looking at it if it is in bad shape? Next Q. The coupler I have is triangle shaped on a 14" flywheel and has a grease zirk on it but no part number. engine is a 87 200hp 305 alpha one I am replacing it with a 350 but should be no difference, it is of the same vintage. The coupler I lloked up is a 18-2175, it says it comes with the new style yoke. if I already have the new style yoke it says to use 18-2323. How do I know if I have the new style yoke? whats the difference?

[yfzjim]

anyone?/

[cr2k]

Look at the couplers splines. If they look good i.e. NOT pointed they are most likely good. If your old coupler and shaft were dry when you pulled it apart it would be a good idea to replace.

Looking at my NAPA (Sierra) parts book, it looks like the diff is this...
If your old engine has a one piece rear main seal you have the correct yoke.

If you have an older 2 piece seal you will need to upgrade to the new yoke.

I believe in 87 you should have the one piece seal.

Either way if your replacement engine has the same rear main as your old one you are ok.

The difference being a slight redesign of the block for the one piece main seal.

Also take your old coupler and fit it on the shaft to see of it is still snug or loose.

Most of the couplers have aluminum splines so proper lubrication (and often) is necessary. Do use a grease made for splines. (Spline grease) This is a more tenacious lube that sticks better and has ptfe qualities.

[wca_tim]

If the splines fit together well and the rubber on the back side (front side actually) looks good, go with it.

[bigskiohio]

i replaced mine and prices were from 85.00 to 400.00 i picked the cheapest to test as replacing it was so easy om my boat. ran it all last week and will see how it looks in a couple of months tungstenmarine.com is where i bought mine
napa,sierra ,glm mallory a bunch out there .

[yfzjim]

so i should be able to get one from Napa?

[myoldboat2]

ouch, tungstenmarine has my coupler for 80 bucks. i just paid 128 for a sierra.

[cr2k]

Sierra Supply is NAPA. You should be able to get a NAPA Marine catalog from your local NAPA store, they may have to order it. Parts, most likely not in store but often available same day or overnite. Prices do vary a little from Sierra.

Part numbers are the same as Sierra.