LT-1 owners: There is a fix for cooling system issues

[gibbons]

Hi All, I am new to this forum, but have lots of MC hours on our 94 205 with an LT-1. It started life with all kinds of cooling system issues, I am surprised I didn't melt it down before I got a handle on things. Way back when, I discovered a fatal flaw in how the engine was applied. I alerted Indmar and MasterCraft, they sent out a service bulletin incorporating the fix I came up with.

With my fix, the engine temp stays absolutely constant within a few degrees, from idle to full throttle. If there is residual interest in this motor or the fix, let me know, and I will take time top post pictures and a scan of the MasterCraft service bulletin (to prove that my info is good). I also have a trick for the heater source and return that I can't take credit for, but perfects the heater. I can share that one, too.

Reply to my post if interested!

[D3skier]

to start off you might want to become a full member of team talk before you go "claiming" you came up with "the fix"

[SkiDog]

to start off you might want to become a full member of team talk before you go "claiming" you came up with "the fix"

I don't recall having seen ANY threads concerning this motor and overheating problems. But I was wrong once before too, so I dunno>!

[flipper]

Was the trick to change the impeller?

[brat]

I would certainly like to see the service bulletin, post it up.

[MIskiboat]

+1 for wanting to see it. I've got the same boat. Please become a member and give the description / pictures.

I've had no real issues, but I'd like to add a heater someday, and the temp always seems shaky the 1st few outings of the year, maybe the thermostats just need to get used to working again...

[flya750]

I have a 1997 LT1 .... 730 hours ... no over heating problems?

The heater doesn't stay warm unless the boat is running @ speed. Do you have a fix for that?

[gibbons]

First off, I just posted my first post today, to see if I had any options for fixing a seam in my observer seat. I started reading some unrelated posts and thought maybe I could be a positive contributor. I don't even know how to sign up to be a full team member. Is ignorant instant sarcasm and skepticism how some of this group treats someone offering a great tip? Gee, maybe I don't want to sign up...

Anyone who doesn't know that LT-1's doesn't know what they don't know. The LT-1 has aluminum heads, reverse cooling, and a cam driven water pump (you knew that, right?). That caused a big problem. It was addressed in the June 1996 Service Bulletin that was generated after my disclosure to MasterCraft and Indmar. Does anyone remember MasterCraft's Nathan Long? I sent him the fix initially. He got Indmar's Alan Tehan in touch with me. Is he still around? He flew in from Indiana and rode around in my boat. He also did some altitude tweaking on my EFI calibrations. Still thinking I'm making something up? I am, after all, just a dumb mechanical engineer.

The overheating problem has to do with aerated intake water and steam in the heads. Wanna know more? Tell me how to fully sign up. If your boat doesn't do it, it may have been built after the bulletin, and had the modification done at the factory.

Yes, I have a fix that will make the heater work full temperature at idle. Absolutely, positively. You will love it. It's a simple plumbing routing. We used to ski mostly in the off season, which meant the water was usually 50 degrees and below. I have wakeboarded while it was snowing, one day we waterskied in the morning and snow skied that afternoon. My family was on the evening news weather for being crazy. Anyway, when it's that cold, you want a heater working full time. Yes, I can show that trick too. But again, I didn't come up with that one. Another LT-1 owner discovered the right plumbing to do it. I showed him how to keep from cooking his motor (the service bulletin topic).

So, if you want more, help me out to get fully registered or whatever. But please knock off with the doubt.

[SkiDog]

First off, I just posted my first post today, to see if I had any options for fixing a seam in my observer seat. I started reading some unrelated posts and thought maybe I could be a positive contributor. I don't even know how to sign up to be a full team member. Is ignorant instant sarcasm and skepticism how some of this group treats someone offering a great tip? Gee, maybe I don't want to sign up...

Anyone who doesn't know that LT-1's doesn't know what they don't know. The LT-1 has aluminum heads, reverse cooling, and a cam driven water pump (you knew that, right?). That caused a big problem. It was addressed in the June 1996 Service Bulletin that was generated after my disclosure to MasterCraft and Indmar. Does anyone remember MasterCraft's Nathan Long? I sent him the fix initially. He got Indmar's Alan Tehan in touch with me. Is he still around? He flew in from Indiana and rode around in my boat. He also did some altitude tweaking on my EFI calibrations. Still thinking I'm making something up? I am, after all, just a dumb mechanical engineer.

The overheating problem has to do with aerated intake water and steam in the heads. Wanna know more? Tell me how to fully sign up. If your boat doesn't do it, it may have been built after the bulletin, and had the modification done at the factory.

Yes, I have a fix that will make the heater work full temperature at idle. Absolutely, positively. You will love it. It's a simple plumbing routing. We used to ski mostly in the off season, which meant the water was usually 50 degrees and below. I have wakeboarded while it was snowing, one day we waterskied in the morning and snow skied that afternoon. My family was on the evening news weather for being crazy. Anyway, when it's that cold, you want a heater working full time. Yes, I can show that trick too. But again, I didn't come up with that one. Another LT-1 owner discovered the right plumbing to do it. I showed him how to keep from cooking his motor (the service bulletin topic).

So, if you want more, help me out to get fully registered or whatever. But please knock off with the doubt.

First of all, we all on here like to have a little fun with EVERYBODY that shows up here. I didn't see ANYBODY doubt what you said, they just said they'd like to see MORE. personally, I don't have an LT-1, so no, I wouldn't know that it has aluminum heads, reverse cooling , and a cam driven water pump. So I've got NO dog in that fight.
Secondly, IF you are a mechanical engineer, you should be able to figure out a simple process for signing up on here. Its NOT hard.
We welcome EVERYBODY, (with the exception of a select few)( and you're NOT in that select few, BTW) to this board! I suggest that you thicken up your skin just a wee bit, join, and have fun like the rest of us do on here. We always like to hear from people that know what they are talking about, even IF we do rag you a little bit.
BTW, what year is your boat? Skidog

[JimN]

First off, I just posted my first post today, to see if I had any options for fixing a seam in my observer seat. I started reading some unrelated posts and thought maybe I could be a positive contributor. I don't even know how to sign up to be a full team member. Is ignorant instant sarcasm and skepticism how some of this group treats someone offering a great tip? Gee, maybe I don't want to sign up...

Anyone who doesn't know that LT-1's doesn't know what they don't know. The LT-1 has aluminum heads, reverse cooling, and a cam driven water pump (you knew that, right?). That caused a big problem. It was addressed in the June 1996 Service Bulletin that was generated after my disclosure to MasterCraft and Indmar. Does anyone remember MasterCraft's Nathan Long? I sent him the fix initially. He got Indmar's Alan Tehan in touch with me. Is he still around? He flew in from Indiana and rode around in my boat. He also did some altitude tweaking on my EFI calibrations. Still thinking I'm making something up? I am, after all, just a dumb mechanical engineer.

The overheating problem has to do with aerated intake water and steam in the heads. Wanna know more? Tell me how to fully sign up. If your boat doesn't do it, it may have been built after the bulletin, and had the modification done at the factory.

Yes, I have a fix that will make the heater work full temperature at idle. Absolutely, positively. You will love it. It's a simple plumbing routing. We used to ski mostly in the off season, which meant the water was usually 50 degrees and below. I have wakeboarded while it was snowing, one day we waterskied in the morning and snow skied that afternoon. My family was on the evening news weather for being crazy. Anyway, when it's that cold, you want a heater working full time. Yes, I can show that trick too. But again, I didn't come up with that one. Another LT-1 owner discovered the right plumbing to do it. I showed him how to keep from cooking his motor (the service bulletin topic).

So, if you want more, help me out to get fully registered or whatever. But please knock off with the doubt.

I was an MC tech starting in late '97 and we had all of the bulletins AFAIK, which I read. I also went to MC training in March of '98. Care to PM me so I know which bulletin it was?

I remember Nathan and it was Alan who developed the training courses, among other things. If it was the bleeder lines or the holes in the thermostat, they were in place before I started working on these.

Welcome to Team MasterCraft but,

You have basically walked into a room full of people who were in the middle of several conversations, without bothering to introduce yourself before saying that you're not sure you like being here. This is your second post, right? No offense, but it was kind of an awkward entry. I don't think anyone will have a problem with knowing about your fix for the LT-1 but to come in, claim that you fixed it without providing anything to support it doesn't really make it so, even if it's absolutely true. I don't know why you would expect total strangers to believe what anyone says just because they say it's true. I doubt you would do this, especially considering your field. You work in a field that would never accept someone's word for any kind of claim without proof, right?

It would be better to get to know the people here before you tell them to not doubt your qualifications and FYI, you're not the only engineer here. We have all kinds of people, from all walks of life and while we may toss odd comments around, the vast majority are good natured. Sure, we have some who don't get along but if we all sat here singing Kumbaya, it would be a really boring place, IMO.

BTW- it's not that hard to look around for the buttons for registration. Here's a link- it's in hte middle of the top gray bar:

http://www.mastercraft.com/teamtalk/portal.php

[gibbons]

I said I'm a mechanical engineer, not a software engineer Heck, if I can post, am I not signed up? What else do I do?

I just spent an hour taking pictures, adding text, and re-sizing them. They are ready to post as soon as I am "signed up". I promise, someone here, if they will listen, will be elated with the changes.

A few notes:

flya750- if your boat is a '97, it probably as (better have) the cooling system changes incorporated from the factory. Hence, no cooling problems.

Also, to show that I am a tinkerer who comes up with goofball stuff that works, here is a link to a Volvo XC70 (AWD station wagons) forum where I defined how to easily change "good for life" automatic transmission fluid. The forum moderator thought it was good enough to put in a permanant "sticky" at the top of the forum http://www.volvoxc.com/forums/showthread.php?t=12169

[JimN]

I said I'm a mechanical engineer, not a software engineer Heck, if I can post, am I not signed up? What else do I do?

If you're an ME and you can't navigate here, you either still use a slide rule or just don't think computers are going to catch on.

I posted a link but I don't have your personal info so,.....

Remember, the head of IBM asked why anyone would want a personal computer, in1959 and in 1899, the head of the US patent office said "Everything that can be invented, has been".

[gibbons]

JimN- Yup, moving the bleeders from the rears of the heads (where they work on cars) to the fronts of the heads. MasterCraft, Indmar, and GM Powertrain all missed that. I guess it's like you can't proof read your own documents effectively, it was obvious to me. It wasn't rocket science, but I caught it. The Service Bulleting was MC96-001, I have a copy that Nathan sent me when it came out. I will post the pics so everyone can check their LT-1's as soon as I am official.

[SkiDog]

Go up to the top right corner of the page , and find the 'log in - register' tab, click on it and follow the directions. Should be cut & dried.

[JimN]

Where were you when they still offered that motor and why didn't you look for this forum?

Seriously, I don't remember seeing very many with repeated overheating issues, mainly because they had either been fixed before I started or because MC/Indmar had already made the changes. If you are/were in Colorado, he did mention going out there for some high altitude testing, but they were doing that anyway. Seeing as it has been 11 years since I went the first time, I'm going to say that I don't remember every detail of every day in class, but I do remember most of it.