Time on your 300x
 

Wondering what kind of times people are getting or overhauling.

Re: Time on your 300x
 

My buddy is at 160 and has had no problems as of yet.

Re: Time on your 300x
 

I had great compression on my 2.5`s 140-144 on all cyl.Boat ran great, then all of a sudden at 240hrs BOOM.I should have listened to Marty at Diamond when he said 150hrs time to rebuild.I guess live and learn(Live and Pay) ,what the hell it just cost me double! :(
Now I am getting ready to pick up my 28 Skater with new 2.5`s that put out 330and 336hp,It is going to be a screamer!
Diamond Marine is #1 for building outboards and rigging in my book!

I know that 300x`s are Supposed to last longer I guess only time will tell good luck. :drink:

Re: Time on your 300x
 

I pulled mine apart for a look at 205 hrs and put it back together nothing needed ! reeds were good no blow by on pistons it was in great shape, now have 260 hrs or so and last time out went fastest speed ever (my best speed) so they are running still strong!

Re: Time on your 300x
 

Jim, do you think using the Amsoil has helped with the longevity of your engs.What is your best speed now?Now I know what ever Marty says is what Steve does.You are right Diamond marine is definately the Only Place to go.Marty should have my boat ready in a few weeks, I am very excited about my new engs and Rigging Marty and Joe have done.

Re: Time on your 300x
 

Use the 100% Pennzoil synthetic, you can get it at wally world sometimes. I order it by the case from oils.com or something like that.

CM

Re: Time on your 300x
 

100% Penzoil synthetic was all that I used ,the previous owner used Klots.Do you have any experience with Penzoil in 2.5`s?

Re: Time on your 300x
 

I have 2.5s after using pennzoil i have not fouled any plugs and it doesnt smoke near as bad. Go to scream and fly its been discussed there tons.

Also everyone says change the ratio from 40 to 1 to around 32 to 1, I go in the middle with 36 to 1.

CM

Re: Time on your 300x
 

Have 340hrs did reeds at 170hrs they looked good. The one bushing on the alternator bracket seems to wear quickly. Compression is good but the engine with the counter rotating lower seems to run less rpm's at wot. think I will swap to other engine to see if it does the same to that one. Anybody else seen this? Nothing but problems with lowers checked oil after every day. Usually changed after every weekend. But without knowing at what point water got in, well you know the rest. I'm on third new set, put expansion tanks on this set guess I'll see if that helps. Engine cowls want to exit in rough water tried adjusting but to no avail. So put 200mph tape on the seam if it is rough. One other thing don't under stand is why my 14.5x30 runs 1mph less than my 14.75x32 lab finshed props. But at the same cruz speed they are 500 to 600rpm's different. Anybody else having these problems or any others?

Re: Time on your 300x
 

My engine cowl has come loose one time, and that was in extremely rough water. I normally dont boat in really rough conditions, so that has not been a problem for me. As far as props, you are slipping the 32's too much if you are only seeing 1 mph gain. Could be a dinged prop, not sure. How far above the bottom are your prop shafts? I would think you boat would run a faster top end with 34's, have you tried those yet. I have had problems with my lowers also. Replaced many prop shaft seals, broke a tooth off of forward gear on the standard rotating lower, and recently cracked the carrier on the counter rotating lower. So far, no prop shaft problems and am still running the small prop shafts.

Re: Time on your 300x
 

I am running 300 promax's but have run Amsoil, Klotz, now just Mercury Premium blend. My motors have a touch over 300 hours and like Skaterjim said, my fastest speed was my last time out also.

Re: Time on your 300x
 

No dings if there is off they go to be fixed. There is some confusion on my part as to exactly now you are measuring. But if you trim motor to 0 or level take a level from bottom of boat to middle of shaft it looks like 7/8 above. But of course you can't do this so this is the middle measurement from the high side vs the low side aka left and right side of the lower unit. Is this correct. Would like to try 34's with the 32's boat has killer low and mid range would give some of that up for some top end.

Re: Time on your 300x
 

Here is how I measure. First the boat needs to be on a level surface (I normally do this in the garage). With the propellor off level each prop shaft, forget what your gauge says. My guages are normally pretty close but its more important to me that both prop shafts are level. Run a level from the center of the nosecone, right at the tip, to the lowest portion of the boat. This will be the bottom of either the right or left sponson depending on which side you are measuring. I have found that my boat ran the best speed at 1 3/4" above the bottom. I am running 300 promax's, I was only running 7-8lbs of water psi, I know the 300x's will not let you run the water psi that low. I have heard anywhere between 1 5/8 to 1 3/4 above the bottom is optimal. Remember, I have the older 300 promax's with the 6300 limiters, and I have run a best of 111.3 gps. To my knowledge thats a pretty good number with that setup. I believe Skaterjim has run over the 121 mark with 300x's.

Re: Time on your 300x
 

Of course these speed numbers are very light on fuel and everything else. As you well know, the 28 hates added weight.

Re: Time on your 300x
 

If you use a laser level it makes it real easy to see where it is above the bottom.

Re: Time on your 300x
 

Thanx I'll check that tonight. All last year I ran props turning in to see if I would gain any mph. Of course the first time I had the boat out 4 200 pounders full of fuel, lunch run. 30 mins into the trip had some nice water so I open it up fastest boat ever went 112 so I figure wow turning the props in made a hugh difference. Little harder to get on plane though and more of a hand full in smooth water. Since then 111 lite on fuel just me does not make any sense. Unless it was the tide, moon, sun spots something like that. Got to admit haven't done alot of testing just out to have fun but after 4 seasons and reading some of the posts on OSO about you guys doing 115-121 with the stock 300x's makes me want to post those numbers. Seems also that a jackplate is about 5-6mph from what I read.

Re: Time on your 300x
 

I went from running 109mph to 117 mph (with some weight) with jack plates, external pick-ups and raising the motors to 1.5 above the bottom. I think I could go another 1/4 inch and maybe pick up a little more speed, but I want to get some weight out of the boat and see how it runs first. With the jack plates the boats rides more level and is less "flighty" in rough water.

I have 60 hours on my X's with no problems, but I have been told the gear cases are the weak point. Lakeland Marine in Havasu makes a vent kit that is supposed to solve the problem, but I have not put them on yet.

Here is a video of mine running 117 on fresh water against a current, and you can see the water is really flat. I want to see 120 this season. You can see how flat the boat runs. Before the jackplates it ran very bow high.

http://media.putfile.com/Skater-Nov-05

Re: Time on your 300x
 

Haulin azz boat looks nice an flat.Yep all the right conditions your seeing 120. Just measured lowers looks to be 3/4 above bottom. Maybe I'm not off as far as I thought.

Re: Time on your 300x
 

Except for the 340 hours I could have writen this myself.
Somebody needs to come up with a pin for the cowls like the 2.5's.
I also ordered the vent kit and will give them a try, for now Im just keeping a set of spares :rolleyes:

Re: Time on your 300x
 

Where did you order the vent kit from? Lakeland in Havasu makes them but I have not seen one yet. Kind of wondering what it looks like.

Re: Time on your 300x
 

GREAT VIDEO!

Good attitude. Where are you placing the weight?

Gerry

Re: Time on your 300x
 

Got mine from a local dealer. Think they ordered them from Mercury. I'll find out tomorrow and also post some pix's. Few things I didn't like was the hoses were only 12" long. What the heck am I suppose to do with that. It's not like they were cheap either. Had to go have hoses made that was another $250. The bulkhead fitting was for the transom not big on drilling into it unless absolutely have to. So had to modify that to. Let's face it we are the R & D'ers

Re: Time on your 300x
 

I was reffering to the Gas I had on board at the time. It was a spur of the moment thing to shoot some video and we were heavy on fuel. I actually though about putting some weight in the sponsons, but since I added the jack plates I don't think it needs it now.

Re: Time on your 300x
 

I will have to see the pics. It sounds like they are supposed to vent into the bilge? The ones Lakeland was making ran up along side the cowlings from how they were described to me.

Re: Time on your 300x
 

Sorry did't get a chance to do it today working two jobs. Seems like the more I work the more the boat takes. Working now be home in the morning definitely get pix's tomorrow morning and post them.

Re: Time on your 300x
 

Think if I was going to do it again I would make it myself.

Re: Time on your 300x
 

Can you explain the purpose for this overflow set-up. Looks like typical outdrive application. Is the hose in the lower unit just tapped into it or is there further work done inside the lower.

Re: Time on your 300x
 

When oil heats it expands when it expands it creates pressure. Overflow gives it some were to go. After running hard I've seen it put as much as 3/4" of added oil in it. Just a fitting in the overflow hole to accept the hose. The hose in the top of the overflow is to see if I can see what the pressure gets to. Just some R & D on my part hose was already there.

Re: Time on your 300x
 

Thanks for the pics. It looks like it would not be to hard to make. I might have to look into just doing it myself. :cool:

Re: Time on your 300x
 

The weak point of the 300x's is the lower unit blowing out seals and letting water in. I have cracked the vent screws after pulling the boat out of the water and there is a fair amount of pressure that is released.

Re: Time on your 300x
 

Amen, been there spent that! If the pressure thing has you worrying I've been told that when the drive cools it can suck water in. "THAT's ALL I NEED" (caddy shack)

Re: Time on your 300x
 

Maybe I need to trim them out of the water between runs. :D

Re: Time on your 300x
 

I just talked to Lakeland in Havasu and their kit runs internal up through the mid section and into the cowling were it vents into a tank. I am getting them done at the end of this month, I will update with pictures.