Tn 28 compression

[toybuilder039]

I am wanting to purchase a tn 28 to restore for 4h project with my kid and we found one we like but first would like to check compression to make sure motor is in good shape can anyone help me out on what the compression readings should be thanks

 

[oldcatamount]

Re: Tn 28 compression

Anything over 50lbs would be good as long as they are within 10% of each other.

 

[nwcove]

Re: Tn 28 compression

you should have a minimum of 60psi on both cyls, or if its higher , the cyls should be within 10%of each other. (some say 15%).
check it and post back, they are fine old motors!

 

[kfa4303]

Re: Tn 28 compression

yup +50 psi within 10% of each other should suffice. Here are some handy links to help you get it running again. Holler if you get stuck. Good luck.....


http://forums.iboats.com/showthread.php?t=158086
http://www.duckworksmagazine.com/07/columns/max/index1.htm
http://forums.iboats.com/showthread.php?t=167352

 

[toybuilder039]

Re: Tn 28 compression

Thanks for the info I am sure I will need some more help to get her going

 

[1946Zephyr]

Re: Tn 28 compression

Nice thing about the TN-28, (1952 - 53)is the ignition parts are readily available, unlike the older TD models. The ignition components are the same as all the other twins and singles built from 1951, on up till about 1974, depending on the model. The impellers are more like the modern type too, which can be obtained at www.vintageoutboard.com. Iboats may have it, but just incase, they don't, I would go there next. Sea-Way Marine is also an excellent source for parts, for all the non-typical maintenence items, such as rings, pistons cranks and such. I just bought enough parts from them to restore an old HD-20, that's more than ten years older than your TN. I think you'll have fun with that old classic.