Compression question?

[Neil Olah]

I'm new here and to rebuilding 2 stroke outboard engines.I have been given a 140 Evinrude model #E140TXCDC all stock.#1 is 80lb the rest are 100lb.What should the compression be?Have not decarbed yet will post results next week!
Thanks for the info in advance!

 

[Utahboatnut]

Re: Compression question?

Ultimately you would want the numbers over 100 on all cyls. Not to say it won't run okay at 100 but that indicates some wear. Also the numbers should all be within 10% of each other so the 80 would concern me a bit. Decarb it real well and retest and post back hopefuly things will come around just a bit.

 

[kenmyfam]

Re: Compression question?

Given !!!!!.........Given.........?????
Send it to me immediately for a free evaluation
Please tell us a little more.
Is it running ???
What have you done so far to it ???
Welcome to iboats

 

[tashasdaddy]

Re: Compression question?

ok, compression testers vary in readings, also the technique gives different readings. the 80 is on the low side for a V-4. good decarb, then recheck read and follow this http://forums.iboats.com/showthread.php?t=313963&highlight=compression. the 1986 140 uses a choke rather than a primer, so you need to follow these for decarb http://forums.iboats.com/showthread.php?t=302825

remember decarbing ruins spark plugs, so install new CHAMPION PLUGS afterwards.

 

[Neil Olah]

Re: Compression question?

I have done the decarb today and rechecked the compression!And got a pleasant surprise my buddy used his compression tool and read 1-110 105-110-110 so I checked mine on his 175 black max and got about the same result.Bad gauge almost ordered new rings and pistons yesterday!Anyways we rebuilt the carbs put them back on pumped the primer ball and low and behold it fired right up didn't miss hick up or nothing!!But now I need a lower unit the case is cracked!

 

[bktheking]

Re: Compression question?

Have it welded by a pro...or just find a case if the internals are good and swap over.

 

[kenmyfam]

Re: Compression question?

How bad and where is the lower unit crack ??

 

[Neil Olah]

Re: Compression question?

How bad and where is the lower unit crack ??

It is cracked on the port side about 2 to 3 inches long almost vertical just off center of the unit and dented in a bit to like someone hit it with a 2lb hammer.Will be difficult to weld. Aluminum is a pain if not impossible to weld when corroded as bad as this is but will try I weld for a living 16 years.The motor came on a 20ft wellcraft deep V.Boat is in excellent condition man just didn't want anymore.He left it in salt water and did not raise the motor out of the water the paint on the lower unit is gone the rest of the motor is like new.Will a lower unit of a 115 evenrude extra long shaft work?Friend of mine has one that he said may work?

 

[kenmyfam]

Re: Compression question?

Try this link for compatability reference.

http://forums.iboats.com/showthread.php?t=359907

Weld job is worth a try, especially if you are an experienced aluminum welder.
Good Luck.