2003 Maxum 2700 can't get on plane - Page 3 - Maxum Boat Owners Club

Phillbo · 10-04-2019, 05:01 AM

Quote:

Originally Posted by golfwins

Ahh, okay. I just got done painting the drive and doing a complete bellows job. I'm guessing it had some air in the line. I didn't do a good job of keeping the reservoir full.

Air in what line?

If your reservoir is puking fluid you have an issue..

golfwins · 10-04-2019, 05:19 AM

You may be right. I've just read others having the same issue after letting the reservoir empty.

I'm not sure what could be wrong. It hasn't happened before pulling the drive for the bellows job and I've been using it weekly.

Any thoughts?

Sent from my SM-G965U using Tapatalk

mmwjr · 10-04-2019, 12:04 PM

If the drive was not filled probably and had an air pocket and the reservoir was then topped off the air will eventually makes its way up into the reservoir and can cause lube to be expelled out the reservoir caps vent. Another issue could be a bad vent, the lube expands as it heats up under use and if the vent is clogged pressure builds up to a point then lube will spew out.

jrsick · 10-04-2019, 01:16 PM

Do you know your prop pitch? RPMs seem low.

golfwins · 10-04-2019, 03:47 PM

Quote:

Originally Posted by mmwjr

If the drive was not filled probably and had an air pocket and the reservoir was then topped off the air will eventually makes its way up into the reservoir and can cause lube to be expelled out the reservoir caps vent. Another issue could be a bad vent, the lube expands as it heats up under use and if the vent is clogged pressure builds up to a point then lube will spew out.

I thought about ordering a new lid this morning, but since it wasn't an issue before I'm going to hold off. I hope it was just an air pocket. Phil's got me second guessing myself this morning, haha.

My prop pitch is a 20P and was just serviced (straightened and polished).

golfwins · 10-07-2019, 03:13 PM

I was only able to perform two tests done over the weekend. I attempted the misfire test, but the ECM555 fires even cylinders with one sire and odd cylinders with another wire rather than 8 separate wires. I still performed the test, but the results didn't show me much. The power drop seemed to be the same.

I also performed the IAC test. It allows you to adjust the IAC from 0 to -100% to 100%. The instructions say that you should hear a change in RPM. The RPMs are also listed on the screen. I couldn't see or hear a change in RPM no matter which part of the chart I was on. I thought the IAC only controlled idle so I'm not sure it's my problem, but according to this test it doesn't appear to be functioning.

Any thoughts on whether the IAC could be causing my problem? My engine starts and idles fine.

golfwins · 10-07-2019, 03:31 PM

Since I can't test each injector individually through the Diacom software, could I just manually pull the harness to each injector one at a time to document the RPM drop?

Any suggestions on a fuel flow test? I know I have good PSI, but not sure if I have good flow. I'm pretty sure I have the cool fuel Gen2 if that matters.

mmwjr · 10-07-2019, 05:40 PM

The IAC only increases the idle rpm when the engine is not up to operating temp. therefore should nothing to do with upper rpm performance.

golfwins · 10-07-2019, 10:08 PM

Rinda Technologies just emailed me and told me that the ECM 555 immediately corrects the Diacom IAC test. So, i guess I can disregard that test.

shrew · 10-08-2019, 02:00 PM

Quote:

Originally Posted by golfwins

It's funny because I met and spoke to a guy in a slip near mine and he said he had the same engine, same problem. He ended up pulling all everything off and carbing it. He said it runs great now. I hope that I don't get to that point.

Don't listen to that guy. He's an idiot.

golfwins · 10-08-2019, 03:27 PM

haha..he seems like a nice guy. I haven't really done a deep dive on this issue yet so I'm not too frustrated. I did think I would have figured it out by now. I'm going to do a deep dive into the fuel system this weekend.

For the fuel system, I've only checked the checkball valve (not sure the technical term) at the fuel cell and replaced the fuel/water separator. I could blow through checkball valve to make it open. I'm not sure what a new one feels like, but it seemed to move freely enough. Looking at some parts diagrams, it seems like my boat has a low and high pressure fuel pump. I don't recall seeing two, but I'll check on that this weekend.

mmwjr · 10-08-2019, 04:50 PM

Anti-siphon valve.

golfwins · 03-25-2021, 01:35 AM

I'm just updating this thread to post the fix. The problem this whole time was a cracked manifold. It must have been spraying water into the 1,3,5 cylinders this whole time. I never felt it struggle into I tried to get on plane. It always started fine and ran fine at low speed. I figured this out because I guess the crack got worse and eventually caused me to hydrolock. After the hydrolock, i pulled the manifold to pressure test it a light went off telling me it could have been my issue with power loss. I replaced the manifold, dropped it in the water today and got on plane with no issues. Thanks for everyone's help!

mmwjr · 03-25-2021, 02:13 AM

Glad the problems resolved but I’m not sure how water from a cracked intake would get into all those cylinders as the only water passage is at the front of the intake that transfers coolant from the from of each head to the thermostat housing.

golfwins · 03-25-2021, 02:28 AM

When I hydrolocked the engine, I noticed that I only had water in the front 3 cylinders. More in cylinder 3 than any other. When I did the pressure test, I could see that the crack just outside cylinder 3. It was probably spraying straight into that cylinder and I guess getting some towards either side. I've seen people do this test before and have a few bubbler here and there, but nothing like this. Here is my video.

https://www.youtube.com/watch?v=SOokfTE2ffo

mmwjr · 03-25-2021, 01:12 PM

Ah exhaust manifold, I was thinking you meant intake manifold.