TOPIC: New Project - 71 Glastron GT-150

Doh, I hate it when that happens!!!!!!!!!!!! At least nothing was damaged and no one was hurt.

Bob

Just my pride, and my jaw hitting the floor when it happened Bob! I think that was "Oh Crap" moment number 63 on this project. LOL (Should have seen this one coming, but we live and learn, right?) Should be fun moving the axle back with the boat still on the trailer, but where there's a will there's a way.

What year is that good looking engine?

What year is that good looking engine?

It's a 1978 E'rude 115 Jim, with PT&T. I've got one more piece of "Bling" to add to it, but I'm waiting until launch day to install that!

Boy, you been a busy guy huh Mark? First time I've looked at this thread. Don't feel bad, took me 4 years from initial boat purchase to getting in the water, and it's still not done yet!

Looks like you did a great job, good for you. Decided to go with Evinrude gas-gobbling power as opposed to (relatively) fuel sipping Merc 1000 power? I had a 115 Evinrude on an old ski boat years ago, and about all I remember is how fast it went through gas! Other than that, it was a great motor.

Get her wet!

Frank

Mark
As long as you put some jack stands under the back corners of the trailer, you should be good to go. Oh yeah, if you have one of those sprinkler doughnuts that you put around the sprinkler head to protect it, use it under the front wheel so it doesn't move. Use a cinderblock under the tongue while you crank the tongue down onto it and get the wheel up high enough to get the doughnut chock under it. Crank the tongue up to remove cinderblock, then crank the front wheel down until the back end is up to the height you want. Put the stands under the corners, crank the front wheel back up and the wheels should come off the ground enough to move the axle. Worst case you can remove the wheels and the axle should be easier to move, so to speak anyway.

Good Luck

Bob

Frank - Yup! Some of the gang here would have has this project done long ago, but I'm doing the best I can with it.

I'm not "anti-Merc" by any means, but I've found my own personal preference is in the cross flow V-4 OMC motors. There are pro's and con's to both brands, I have much respect for both "camps".

Bob - That's pretty much how I got her up on the jack stands this morning before work. Both trailer tires are just off the ground, and she's supported on stands securely (2 aft and 1 forward). The issue is going to be that the Holsclaw uses the axle as the support for the forward bunk arms, had I left the original "roller racks" on there it wouldn't be a big deal. They were drilled like the frame so you could move the axle easily. My wooden bunks however, have fabricated brackets to secure them to the support arms, so I'll have to remove the brackets and drill new holes in the bottom of the bunks to remount them, then move the axle back and re-attach. I'm thinking of picking up the stern of the boat with my engine hoist and a sling to take the weight of the boat off the bunks while doing this, I don't want any "mishaps" at this stage of the game!

Sounds like a good plan to me.

Bob

Got the axle moved back to the rear position, much better balance now. (Ended up lifting the boat off the trailer with the engine hoist on the stern, come-a-long on the bow.) Gotta love the old Holsclaws and their built-in adjustability!

Made a few final adjustments this morning, and headed to the lake. To quote a phrase from "back in the day", WHAT A RUSH!

I've got some serious chine-walk issues at 53mph, had to back down from there. Not bad for the first time out, though.

Outstanding Mark, she looks awesome!!!!!!! Thanks for brining us all along for the ride!!!

Bob

mark you have a great looking rig there buddy,john

Outstanding job Mark !! I assume your heart was beating a bit faster than usual yesterday ? What a thrill and congrats !! So glad this one got saved and the video was great ! Were you on your knees ? If so I hope you had something soft to kneel on ! 53 MPH Wow ! That chine walk will come on fast !

All the best with the finishing touches !!

Thanks for the kind words guys, much appreciated. Sorry for the delayed response, been having computer issues (my end most likely) and getting "bumped off" the site the last couple days!

Probably being "bumped" 'cause nobody wants to be outdone with your super looking resto !!

Very nice Mark. The video made my morning. That makes a pair of nice Glastrons. That motor sounds like its only hittin' on four cylinders. (All in jest Mark, looks and sounds great).

Very nice Mark. The video made my morning. That makes a pair of nice Glastrons. That motor sounds like its only hittin' on four cylinders. (All in jest Mark, looks and sounds great).

mark,i just watched the video with my wife lorraine,wow what a rush,especially since shes not that fond of water,lol.great thread and a great job,beautiful boat buddy,john

SMOKIN! What a thrill ride, thanks for sharing.
Cal

Just catching up on some pics of the project updates, knocking out a few more small details;

mark, nice to see you making waves. great video, had to watch it a few times. you have a very nice boat. frog

Nicely done Mark, tucked away all nice and neat!!!!!!!!

Bob

Mark, now that's what I call ship shape, nice and clean!
Cal

Thanks guys, I'm trying my best to do the old girl justice. Took her out again yesterday for some training (me) and prop testing (OMC 12.75x21P alum). First one is just a cruise with a short blast at the end;

Boat control at (close to) WOT takes both hands, I was trying to document the speed as I "snuck up" on the chine walk;

(Bumped 55mph, we'll call it 54)

Having a ball, but a windshield is going to take priority over finishing the interior! (That's just a temporary seat, not even fastened down!)

Looks like you might be having a little fun with your old new toy !

I seem to remember a few early emails I received from you about a year ago when you were sort of inquiring about the possibility of getting the old girl...Well, looks like you accomplished the goal ! Congrats and get that wind screen hooked up !

I stumbled across this forum and discussion thread and found it interesting enough to join the forum.

I have a '79 GT-150 with a 2000 115 Johnson. My son gave me the boat for my birthday about 3 years ago. I got the 115 Johnson to replace the '74 85 Evinrude with manual trim (yuck!!) that came on the boat.

I've been doing a lot of work to try to limit the chine walking issue that I too, have been experiencing. The first thing I did was to get rid of the transom well mounted steering, and converted it to tilt tube steering. That got rid of about 75% of the slop in the steering mechanism.

The next thing I did was start experimenting with several props, and I discovered something interesting. Raker or so called "performance" props actually exacerbate the chine walk issue. The best running prop I have is a 21" OMC SST. It seems that using a "bow-lifting" prop makes the chine walk dance quite a bit worse. Using the 21" SST, I have seen 54 mph measured on a Garmin GPS.

Here is another video better showing my '79 GT-150:

Thanks for the "shout out" Tail Gunner, and welcome aboard. Good looking GT you've got there, and thanks for the input/info. Been working on getting my windshield installed, hope to have done in another day or two.

I've got a 12 3/4 x 21P SST prop coming in today, hope to give it a try this weekend. (Finally found my GPS unit that was hiding in the garage!)

Beautiful day for a boat ride, but a little too windy for any serious prop testing.

Mark, I needed that. Thanks for the ride. Beautiful looking rig.
Cal

Mark,
Outstanding.Boy she really does look great in her natural habitat, looks fast just sitting there! Did the same thing myself, only not as fast. LOL Starting problem is still there but we still had fun. I'm hoping to get out next weekend too. Sorry didn't take any movies, don't have an account on you tube.

Bob

Nice little video!! I love the sound of an outboard going full throttle on a GT-150!!

I found that my GT-150 does not like a lifted bow or too much trim out. (That's why Raker or bow-lifting props don't seem to work as well as standard SST props) The dreaded "chine walk" monster begins to rear it's ugly head when I trim out too much. So far the best way I've found to get that last possible mph out of it is to floor it with mid-range trim about 45 mph. Then trim out with tiny little "bumps" of the trim button. The chine walk will begin to slowly develop somewhere past 50 mph. Then I "bump" the trim down once or twice and that is about all you're going to get out of it. So far 54.something on GPS is the most I've seen. I think it's important to note that the magic trim point is something short of full out trim. Also, my motor is a 2000 115 Johnson which FWIU, has about 20 degrees of trim range. It looks like you have an earlier V-4 which has a smaller amount of trim range or about 15 degrees IIRC. So your "magic trim" point may be full out on your engine.

Due to the commonality of chine walk about 52 mph reported by many GT-150 owners, I've become convinced that it's a hull design characteristic and not steering or motor mount slop. Without a pad, I don't see how a GT-150 will see anything over low to mid 50's on the speedometer or GPS.


FWIW: The pic of my boat shows the old 74 85 Evinrude on it before I swapped it out for the 115 Johnson.

Once again I appreciate the info, and with what little experience I have had so far I understand what you're saying. Since I'm new to power trim and this hull, I'm learning a lot every time I go out. So far about 1/4 trim is all I've mustered, but I'll have to give your prescription a try. I'm learning that the little bumps on the button make it easier to control, just going to take some experimenting and practice.

Raising the motor another hole has been suggested, seems to have all but eliminated the chine walk for Honker! I may give that a shot during the off-season. Even if I don't raise the ceiling any from here, I'm having a ball so it's all good.

For anybody who hasn't done "the dance of death", a little taste of chine walk at the very end of this video;

Yep, that was getting a little hairy towards the end of the video.

I'll bet it was worse than it looks because of the way your camera stabilizes the video and horizon/far shoreline.

BTW, what setup are you using to take the video? I like the way it stabilizes the picture going over the bumps.

It's just a fairly inexpensive (under $100) Sony digital camera I've had for 5 or 6 years, but it does do a pretty decent job. It's got some sort of "stabilization mode" built in, does it all by itself. (I'm just a point and shoot kinda guy!) I'd like to make a mount for it with suction cups or something, would make it a lot safer than driving with one hand.

Things have been pretty hectic and stressful at work lately, so I took a day off to have some "quality time" with my baby. ~ New carpet installed. New seat frames glued and screwed together, glued to floor (last weekend) with 5200, NO screws into this floor! Trimmed them in.... After cutting the 10" tall bases down to 4", the new seats were set in place. I couldn't afford the upholstery bill for re-creating the exact replacements for a true restoration, heck I couldn't even afford "store bought" back to back lounge seats. These were some jump seats I caught on sale last winter, I think they turned out okay for a "first timer".

Nothing wrong with that Mark. We all do what we have to do. I think they look great!!!!!!!!!!!!!!!

Bob

Well I ended up cutting another 1 1/4" off the seat bases, trying to get the wind out of my eyes while underway. (Short windshields don't offer a lot of protection.) Still have a few odds and ends to finish up, but I'd say she's 95% complete at this point. Played with weight distribution and different props, still have a little "tweaking" to do during the off-season on the motor set up. Got a very respectable top speed out of her today though, I'm pretty well satisfied with the number for now!
Prop Test Results to Date;
Mission is to get WOT at 55-5600, with max SAFE speed. (Looking for 55!)

Starting point/baseline - 1st Prop - OMC brand 12 3/4 X 21P ALUM - WOT 5400 @ 54MPH - Note: gets a little hairy over 53mph, nature of the hull design as I am told.

2nd Prop - OMC SST 12 3/4 X 21P Stainless (teflon coated) - *WOT 5200 @ 52MPH - Note: more left on the table in the speed, *chine walk gets too severe to continue. Porpoising at lower speeds if trimmed above 1/4. Probably going to be the fastest/best all around, if the set-up can be refined to control the boat at top speed.

3rd Prop - OMC Raker 13 3/4 X 22P Stainless - WOT 5100 @ 50MPH - Note: Too much pitch & bow lift, didn't like much if any trim, porpoise and chine walk prevalent, much better suited to CVX style hulls with pad.

4th Prop - OMC SST II 13 3/4 X 19P - *WOT 5800 (pulled back, was still winding up!) at 48MPH - Note: not enough pitch, might be a good prop for heavy loads or pulling barges.

5th Prop - Power Tech PT03(?) 13 1/5 X 19 w/custom cupping and pitch added - WOT 5200 @ 48MPH - Note: Stern lift created by this prop gives a whole new "feel" to the boat, thought we had it here. RPM and MPH just not where they need to be.

Back to props 1 and 2, with a Solas Amita 3 13 X 19P as a back-up/spare/emergency. Will probably try raising the motor up another hole as suggested, and maybe add a Bob's True Tracker to help with stability. All numbers posted from recollection, so please forgive me if they're not exactly as stated earlier.

Special thanks to David P. (CGOAMN), & Tim at Performance Props Inc - Soddy Daisy, TN.

SWEET!!!!!!!!!!!!!!!! Way to go Mark, that should be a lot of fun. A lot more than the 26 I'm getting. i guess I really need to get that 80hp running and in that '61 housing.

Bob

I just read your entire thread... Let me say what others have said, "Great Job!"

I love that you weren't too wrap up in originality and did things that met your level of expertise and finances. That Glasstron is amazing!