View Full Version : LT-1 and Perfect Pass Install
04-12-2011, 04:49 PM
I can't thank you all enough for everything I've learned on here. This forum is one of the best parts of Mastercraft ownership.
Now to my problem: I bought a Perfect Pass system for my boat (1998 Prostar 190, LT-1 engine) and I'm having trouble finding a good location to mount the servo motor that controls the throttle. In a typical installation it mounts to the starboard exhaust manifold water feed, but in the LT-1 the line is significantly lower. Every way I've tried mounting it seems like it will make the cable bind.
What I'm hoping for is someone with an LT-1 and perfect pass can post a pic of where they mounted the servo. Doesn't have to be all that detailed or high quality, just need to see what hose its on and the rough angle.
Thanks in advance,
east tx skier
04-12-2011, 04:59 PM
Can you mount the servo in the typical location and then rotate it up or down on around the hose so that the cable is higher or lower (hard to tell from your description which part is lower)? This will give you a little bit of play in the height of the throttle cable from the servo and hopefully even it out. Alternatively, is there a way to adjust the height of the throttle cable? I upgraded the exhaust manifold on my old MC and had to use a bracket to even out the throttle cable height to keep it from binding.
04-12-2011, 07:25 PM
Here ya go. Never had an issue with the cable routed this way. Worked well despite looking like it was kinked a little bit.
I always had more issues with the electrical side of PP and also got sick and tired of the display falling off the bracket all the time so I don't use it any longer...
04-13-2011, 03:43 AM
Thank you JLeuck. I knew I could count on the community here. That looks like it should work fine. I didn't try it that close to the manifold. While we're at it, does anyone else have any other mounting locations for the servo, or is this pretty much the conventional wisdom?
Also, I love that anniversary edition blue LT-1. Its gorgeous.
Totally off topic, but it looks like your head bleeder line is on the front and it looks factory. My 98' had it on the back. From what I've read I thought that they knew a few years before that it didn't work very well letting the air out of the head when it was on the back. Most of the others seem to have them on the front by then. Mine seems to be a strange one. Just thought that was odd.
04-13-2011, 09:33 AM
There are some thread tools at the bottom of each page that will let you expand the number of threads you can view. So if You start from the engine/drivetrain menu and expand it to show everything for the previous year there should be a few threads about LT -1's overheating. Some of those will reference moving your lines to the front of the risers and cylinder heads. Good reading for sure!
04-13-2011, 11:06 AM
About the crossover/bleeders; they should be on the front.
Here is a thread detailing that:
The strange thing is that this problem was mostly on the ealiest LT-1 engines late 1993-early 1994 production...your's seems very late for this.
Anyhow, good luck! You have a great engine!
04-13-2011, 06:47 PM
I guess I left out that I found those threads in the fall and moved the bleeder line to the front over the winter. Good looking out though. Thanks again guys.
04-13-2011, 07:34 PM
I had the exact same problem on my install. I was not at all satisfied with the hose mount system. I built a stainless mount that attaches to the engine head. I then made a slide for the cable because I also did not like the way that was designed. This is an old picture, and if you need more info, I would be glad to help.
04-13-2011, 11:36 PM
You are the man, Eddie. Your install is what I was hoping to find. Can you take some pics of the mount you made? What is the slide you're talking about? I'm guessing it's the copper-colored thing. It looks like it has some sort of bent rod holding it up? Is this to control the radius of the bend in the cable to make it a smooth curve?
04-14-2011, 04:06 AM
I am working long hrs and it will be Friday evening before I will have time to take some more pictures. On the slide, I did not like the way that the cable was just hanging with nothing to support it. I used a piece of tig wire and copper tubing. I split the tubing and installed over the cable. I squeezed it back together. I then bent the tubing to match the natural curve of the cable. It just rest of the tig wire and slides back in forth with the cable movement while supporting the cable.
04-14-2011, 03:44 PM
Love the slide idea. I'm definitely going to fashion one of those. No rush on the pics of your mount. I won't get any time with the boat this weekend so it will be next weekend before I'll be back in the garage.
I know we probably would have been ok to just mount it lower and live with it, but I'm glad to find someone on here who's a perfectionist like me to figure out a better way. Not settling for good enough is why we are MC owners, right?
east tx skier
04-14-2011, 06:59 PM
That's a great mod, Eddie! Nice judges display, too.
04-18-2011, 08:58 PM
A couple days late, but you said take my time. The bracket is nothing more than a piece of S/S angle that I cut up some. I left the angle complete on the end where the pipe is so I would have something to weld to. The pipe is about the size of the hose. That way I did not have to modify the bracket on the stepper motor. I just tack welded the pipe and mounted it, adjusted angle, removed and welded.
The slide bracket at idle position.
The slide bracket at full throttle.
Hope this helped.
04-18-2011, 09:05 PM
That's a great mod, Eddie! Nice judges display, too.
Thanks for the reply. I have posted about the judges display before, but just a quick comment. It is a display and controller. I have a switch to swap from the in dash controller to the judges display. I made a mount on top of the boom adjuster and it has Velcro so I can remove and use it while in the observers seat.
04-19-2011, 01:34 AM
Thanks so much for posting those Eddie. Really clean install. Looks like I'll be using both of your ideas on this one. When I patent it and sell a million of them I'm claiming all the credit. I'm sure the market for mid-90s MC's with LT-1's and perfect pass that happened to be owned by people like us is easily in the 500k range.
Looking at the pictures it looks like your head bleeder line is still on the back. Have you had any of the temp issues the other guys talked about?
04-19-2011, 05:38 PM
Yes, the air bleeder is still in the back. I understand that this could be an issue. I have never seen the temps over 160. It is rock steady. I clean all water lines and replace the impeller every year. I do not hot rod at all, and 34.2 is what my son and I both ski at. It never exceeds that speed. In other words, I baby it and I also maintain the maintenance on it. That might be some of the reason I have never had a heat issue. I will just leave it alone for now. But thank you for asking, because it could have very well solved a problem if I was having heat issues.
Forgot to add, if you do not have any, pick you up some never-seez to add to the bolts threads that go into the head.
04-20-2011, 12:04 AM
Well if you've never had temp issues, I'd have to fall back to some of the best advice my Dad gave me: Don't fix it if it ain't broken.
Good call on the never-seez.
04-22-2011, 08:23 AM
Well I was wrapping up the install last night. I pulled the little piece of protective tape off the display before I turned the key on and my display has a big dark bubble in it. I hoped it would go away when it turned on, but no such luck. I've emailed perfect pass already. Looks like I got a bum unit. I imagine it will be a few days before they can mail me a replacement.
In other news, did either of you guys use the throttle return spring that PP provided or is the motor ok without it?
04-24-2011, 08:22 AM
I do not recall a throttle return spring. Itís been a few years since the install and I have trouble remembering what I did yesterday. I just grabbed this picture from the web to show the only spring that I am using which is the original one. Really, the only reason that I can see for the return spring is if the cable comes loose from the throttle body. Without seeing your setup it would be hard to comment use it/ donít use it. I will just say for safety reason, you do need a return spring. It can be the stock original or aftermarket.
05-16-2011, 05:45 PM
Here's a 1998 specific question. I'm having some issues with the gas struts/springs for the observer seat and the rear trunk. The rear trunk has two different weight springs in it. One side is a 15, the other is a 20. What is the stock weight?
The observer seat is an even bigger mess. The PO gave me a box with about 10 different weights in it for the seat, but some are new and some are worn out. I can't seem to find a combination that holds the seat up without being overkill and stressing the mounts. Can some one please tell me what the stock weights are? I've got everything from 20# to 120#.
I have a 1996 ProStar LT-1 and I installed the PP myself. I had some issues related to the cable travel. You want it 90 degrees to the throttle connection so it doesnt skew,but you have to compromise, because the angle changes with the travel. In my case, the travel of the cable would snag on the optional heater valve (a regular hose bib fitting), so I cut an oblong piece of thin cutting board material to allow the cable to have low friction when sliding across it. I also repositioned the servo and angled it down. at one point, the travel could also contact the front of the engine cover. so check your install and make sure these travel problems dont apply.
You want the alignment of the throttle cable to be straight on to the throttle travel, ie not too much of a bend.
05-18-2011, 02:47 AM
Thanks tjb. I built a mount like Eddie did, so I think I got the cable travel issue solved. His mount and cable slide are the slickest thing I've seen to make it work smoothly. I know that its overkill, but again, overkill is why I bought a MC.
I got the system all installed and working perfect. I've had to add a pair of small vicegrips on the cable to add some tension to keep the throttle from returning to idle on its own. I'm looking for another source for the real cable clamp since skidim wants 20 bucks plus 12 bucks shipping. I can buy a small pair of generic vicegrips for a third of that. What can I say, I'm cheap sometimes. For now, my redneck engineering is working. If anyone has found a better way, let me know.