240 EFI M2 500 hour maintenance

[johnhibbs]

I would recommend two things to do after 400 or 500 hours of use. Get a new TPS sensor and change the head gaskets (o-rings). While troubleshooting my TPS probem the local mechanic said my problem was the head gaskets. I'm glad I didn't pay him $2K to not fix my problem but I did it myself to not fix the problem. The good news is that my Mercury parts dealer said that the o-rings only last about 500 hours so I'm glad I did it. There is an 0-ring for each cylinder plus a bigger one that goes between the outside of the engine and the water passing section. All 7 o-rings did needed replacing. The big one was really bad. I'm sure it's a big problem when water gets in the cylinder. It only took a weekend and the compression is up around d 140 PSI on each cylinder.

I bought a ratching wrench called an x-beam ratching wrench from Sears. I couldn't have done it without it with the engine still in the boat. It is a rachet wrench with a swivle head with the ratchet part is inside the head of the wrench. It is a very low profile wrench to get in hard to get places. I must admit something bad though. I used a torque wrench on half of the bolts and I guessed on the other half. A snap-on socket won't fit on a torque wrench and get where you have to get to. Also the heads have a note saying not to reuse the bolts. I did it anyway. No heads broke off but you can buy new ones if you want. I'm too cheap and wreckless.

 

[Thunderkat13]

awesome work but yikes on reusing the original head bolts...
Im not sure on boats, or the seadoo's, but on most automobiles the manufacturer uses TTY bolts... Torque to yield, meaning that you tighten the bolt to almost failure and then back it of a 1/4 turn to ensure proper torque specs

 

[johnhibbs]

90-degrees wrong way

I just read the manual again and it said "30 ft lbs and rotate 90" I thought it meant to increase it another 90-degrees after the 30 ft. lbs. OOPS. Thanks for pointing out which direction to turn the 90-degrees. As you can see I've never worked on engines before. This is my first boat and first engine. I almost got it right. Plus i's probably a good idea not to use the bolts again. There are 24 of them though. I don't know if they can be bought somewhere else than a Mercury parts store.

 

[Thunderkat13]

Hey John, Im not sure on boats either, Im just talking about in my past experiences....
Im not sure if you need to back off with a 90 turn or tighten more with the 90...
Hopefully someone else will chime in, or the manual will enlighten you ..

 

[rookie101]

You did it the right way. It is always an additional turn after the initial torque is reached. This removes all stretch from the bolts which keeps the torque even during the heating and cooling of the engine.


Aaron:cheers:

 

[johnhibbs]

Need a TPS for a 240EFI M2

I need a TPS (PN:14851004 or a 14852). The factory has been on back order for over one year. I'm contacting a bunch of dealers via email and I'm hoping someone will have one in stock. I started on the East Coast since that is where I think most of these boats are. I would also be willing to buy a used one. Thanks.

 

[rookie101]

Just checked Crowley Marine, and they say it ships in 3-5 days. Give them a call and see if how fast they can get it to you .

http://www.crowleymarine.com/mercury_parts/4879/110.cfm


Aaron:cheers:

 

[johnhibbs]

TPS on back order

I just called them and they don't have any stock. I understand the factory has been on back order for over a year. I'm trying Sugar Sand Dealers too.

 

[johnhibbs]

Replace wet exhaust hoses!!

I finally found the problem with my Challenger with the 240EFI M2 engine. I either replaced, cleaned or inspected almost everything on the engine except the ECU and control unit. While out on the water and monitoring the fuel pressure my son noticed that one of the exhaust hoses expanded like a ballon just when the rpm dropped.

I took off the hose and looked inside. The inside wall had delaminated and a huge blister had formed. Since both water and exhaust flow thru the hose the water was probably filling the blister and blocking the exhaust. I then check the other hose and it had the same problem. I replaced both hoses with www.tridentmarine.com wet exhaust hoses and the boat runs like a jet ski now.


The hoes may look fine on the outside but the inside may be coming apart. If the hose feels soft at the bend it's probably bad. If you idle the engine and hold the hose at the bend you can feel something vibrating inside. This hose was the cause of a Seadoo recall related to salt water spray on the throttle.