can I swap 270 with a 290 ?

[ffleury]

Hello,
my 270 outdrive is damaged and I found a 290 . I have heard that it depends on the 290 but it can be as easy as 2 hrs for some of the models . The 290 model is 857949 and SN is 1101505600 . Is this true ? What should I be looking for or at ?

Thanks
Franck

 

[Don S]

Re: can I swap 270 with a 290 ?

If you are asking about taking a complete 290 drive and putting it in place of a complete 270 drive. No. Not going to happen.

You can change the lowers for sure as long as the lowers vertical shaft bearing race is re-shimmed to the 270 intermediate housing.
And depending on the upper and how the helmet bolt setup is and if the vertical shaft bearings are the same kind as the 270, it could be used too.

Have no way of looking up those model and serial numbers to see what they go to. A dealer with the dealer program can, but I have never found anything on the web that will do it.

 

[ffleury]

Re: can I swap 270 with a 290 ?

thank you Don... so I will look for a lower unit 270 and 280 but do I have to re-shim as well if I replace the whole lower unit ?

 

[Don S]

Re: can I swap 270 with a 290 ?

thank you Don... so I will look for a lower unit 270 and 280 but do I have to re-shim as well if I replace the whole lower unit ?

Assuming you mean the complete outdrive, instead of just the lower-unit, then no you do not have to shim anything.

 

[ffleury]

Re: can I swap 270 with a 290 ?

Just to make sure i fully understand : If I change the lower unit only on my 270 that has 280 lower unit , do I have to re-shim if I put a 270, 275, 280 or 290 lower unit ? ( in these cases I would exchange the lower unit only with one with the same ratio).
If the answer is yes , I guess I would like to understand. If the answer is yes, then finding a complete full unit , although more money should be a lot less work . Right? In that case, a full unit exchange choices that are a drop in are what ? 275 and 280 with same gear ratio ? or is there an adaptation needed ?

 

[jerryjerry05]

Re: can I swap 270 with a 290 ?

The lower unit ratio must be the same or the lower unit swap won't work for your engine.
2.15:1 for the 4 cylinder, 1.89:1 for the inline 6, and 1.61:1 for the V-8.

Make sure that you are not confusing a 250 for a 270. The 250 is small bearing.
The 270, 280, 285, 275, 275A, 290 and 290A upper units are all mid size bearing.
The 270 upper unit can be swapped for a 290 if the female yoke is changed to course spline, and if the helmet is changed to accept the double bolt helmet pin.

Re-shimming must be done anytime when changing an upper unit or lower unit to a different intermediate housing.

If you want to use the complete 290 drive, do the yoke and helmet change, and also remove the pivot tube, swap the 290 suspension fork and anchorage bracket for the 270 fork and reverse latch unit.
No re shimming needed.

Install the upper unit by itself and last.