well heres a vid of my lap cat 2
#1
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well i found it on a site and the guy said hell take 200 comes with everything in the pics. and i believe its a tunnel hull correct.(sorry first boat) im big in to rc racing and such so i know my rcs but never had a boat. what u guys think?
and heres his add.
Motor is a 7.5cc K&B outboard. Has a motor mount adjustable jack plate. Brass two bladed speed prop along with others. Pistol grip radio. This is a sport and racing boat and will do real speeds around 60 MPH. Length 37" Width 20 1/2" Boat stand / work station comes with eletric starter, fuel pump, spare props, tools, extra parts never used aswell.
http://www.youtube.com/watch?v=Go9iAvYoX7Q








and heres his add.
Motor is a 7.5cc K&B outboard. Has a motor mount adjustable jack plate. Brass two bladed speed prop along with others. Pistol grip radio. This is a sport and racing boat and will do real speeds around 60 MPH. Length 37" Width 20 1/2" Boat stand / work station comes with eletric starter, fuel pump, spare props, tools, extra parts never used aswell.
http://www.youtube.com/watch?v=Go9iAvYoX7Q









#2
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well I hope your a good mechanic cause you'll likely need to take the motor apart and replace the bearings before you start it.
That carb will probably have to go too for something more consistant,, Rod Geraghty has carbs that are much better.
The prop looks very dull, although I can't be really sure,, sharpened and balanced is the key.
60mph? possible but not likely
That hull don't mind going straight but cornering is going to be a work in progress.
$200 for all the stuff ain't too bad but initial costs before running will bring that number up.
Thats a very old motor and to be absolutely honest they can be a near futile venture.
Good luck
That carb will probably have to go too for something more consistant,, Rod Geraghty has carbs that are much better.
The prop looks very dull, although I can't be really sure,, sharpened and balanced is the key.
60mph? possible but not likely
That hull don't mind going straight but cornering is going to be a work in progress.
$200 for all the stuff ain't too bad but initial costs before running will bring that number up.
Thats a very old motor and to be absolutely honest they can be a near futile venture.
Good luck
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for a first project boat and to learn from it will be fun money i dont mind spending but well see how it goes. im about to leave and go get it
#5

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It's OK for $200.00 but the hull and radio system are antiquated so it's not a racing boat. I highly doubt if it will hit 60 down a greased mineshaft much less on the water. You might see high 40's but that's it.
Keep in mind that you have to reverse the polarity on the starter as these engines run backwards from normal.
Let's see, Prather hull, Prather motor mount and a Prather servo saver is what they call those 2 pieces at the top of the lower unit. Toss those away. You're going to learn to hate that motor mount also, it's a real hassle to adjust anything and keep it there.
Another heads-up. You're going to have to remove the propshaft to grease the cable inside, it's got left-handed threads.
Keep in mind that you have to reverse the polarity on the starter as these engines run backwards from normal.
Let's see, Prather hull, Prather motor mount and a Prather servo saver is what they call those 2 pieces at the top of the lower unit. Toss those away. You're going to learn to hate that motor mount also, it's a real hassle to adjust anything and keep it there.
Another heads-up. You're going to have to remove the propshaft to grease the cable inside, it's got left-handed threads.
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well believe it or not but the only problem i had was the carb was stuck shut and was pritty damn hard to open, i put some fuel in a sup and let it soake for a while and then it sarted to loosen but the damn piston looks brand friggen new(pics later) but now u haid i would need to greese the prop cable thing now i took it out well the shaft and i see greese in their, can i use any greese or what also i see where the exhaust port is but where does it come out of the outboard
and the carb is bact to normal also the only thing that it didnt have was a carb gasket but i had gasket maker stuff so that good. also i swaped out the old receiver of my spectrum. quick question: what is that little leaver sticking out of the carb? is it like the high speed needle?
and the carb is bact to normal also the only thing that it didnt have was a carb gasket but i had gasket maker stuff so that good. also i swaped out the old receiver of my spectrum. quick question: what is that little leaver sticking out of the carb? is it like the high speed needle?
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Little lever out of the carb of a K&B bent in an L shape is the HS needle, personally if you get it running well and boat all tuned in correctly that will make a decent first boat, old school or not, its not the fastest but should be fairly reliable and teach you a great deal about RC boating, also since people on the boards jump to racing all the time(im guilty of it to) there is a chance that boat could very well take place at the end, boat racing works on a points scale not necessarily a whos fastest wins scale, tuned to the gills for 100% reliability and max output topped off with a good driver has every chance in the world to place..
radio is a bit out of date I agree on that but if it works run it, wasnt that long ago all the RTR's ran AM stuff
radio is a bit out of date I agree on that but if it works run it, wasnt that long ago all the RTR's ran AM stuff
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JWMODS...Dude! Why would you say that to the guy without knowing anything about the engine? Its his first rc boat and i think its a steal for $200 bux for what hepaid for.
Bigstang,
Engines that sit around for awhile are going to get gummed up so yeahsoak it in wd-40 or whatever your fav juice is, THEN see if theres anything wrong with the engine....Its looks pretty clean outside, not beaten up. I've seen alot of older engines that if properly cared for look very clean inside so to see a newish looking piston is common. I would look into a replacement prop that has been balanced N sharpened just to have some piece of mind knowing that the prop is ok. Just look at the props hub and it will have the part number. Octura X442 for example or similar.
That radio is just fine for now. We used those am radios back in the 80's and there really wasnt ever any issues with interference, dont let the speed demons here on the forum get to ya, you have a decent setup and its a good running hull and those k&b .45's are very reliable engines. You can if you wish upgrade to a Futaba 3pm Fm radio which can be had for about 180 bux or so, you can probably just continue using the servos thats already in there if they work ok, just swap out the reciver...
I agree 100% with toyotatruckin's comment. Just clean it up and put 'er in the water...It looks like an older Prather Lap cat II and those were very good boats in their day and a great way to get into rc/boat racing.
Bigstang,
Engines that sit around for awhile are going to get gummed up so yeahsoak it in wd-40 or whatever your fav juice is, THEN see if theres anything wrong with the engine....Its looks pretty clean outside, not beaten up. I've seen alot of older engines that if properly cared for look very clean inside so to see a newish looking piston is common. I would look into a replacement prop that has been balanced N sharpened just to have some piece of mind knowing that the prop is ok. Just look at the props hub and it will have the part number. Octura X442 for example or similar.
That radio is just fine for now. We used those am radios back in the 80's and there really wasnt ever any issues with interference, dont let the speed demons here on the forum get to ya, you have a decent setup and its a good running hull and those k&b .45's are very reliable engines. You can if you wish upgrade to a Futaba 3pm Fm radio which can be had for about 180 bux or so, you can probably just continue using the servos thats already in there if they work ok, just swap out the reciver...
I agree 100% with toyotatruckin's comment. Just clean it up and put 'er in the water...It looks like an older Prather Lap cat II and those were very good boats in their day and a great way to get into rc/boat racing.
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Prather Lap cat II that is is. and now im putting it back together so tomorrow i can run to the hardware store and buy a 3 screws. then in the water she goes. also get a few more plugs too. yeah around me thier is no racing so it will be a fun boat. also what kind of paint should i use?? its a fiberglass boat so auto paint should work just fine right??
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you asked where the exhaust came out from!
if you look at where your brass pick up tube is (water pickup) you will see 3 or 4 holes below it, thats where the exhaust exits.
I too started with an old school 8 or 9 years back, it was a Dumas Hot Shot 45 with a K&B 7.5 like yours.
it was built like a tank and heavy like one, but it didn't matter, I paid $75 bux for it in a yard sale and I ran it for 2 years.
I had my fun, learned a lot, sold the engine and moved on to better and faster boats.
enjoy.
Dan.
if you look at where your brass pick up tube is (water pickup) you will see 3 or 4 holes below it, thats where the exhaust exits.
I too started with an old school 8 or 9 years back, it was a Dumas Hot Shot 45 with a K&B 7.5 like yours.
it was built like a tank and heavy like one, but it didn't matter, I paid $75 bux for it in a yard sale and I ran it for 2 years.
I had my fun, learned a lot, sold the engine and moved on to better and faster boats.
enjoy.
Dan.
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hey thanks guys for all your help. and dan thanks for the exhaust, thats what i thought they were but didnt know. maybe in the future ill look for a newer hull and swap everything over but who knows lol
#13

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You asked about what to use to lube the cable with so I'll address that.
K&B recommends a 50/50 mix of 20w50 and STP but I've tried that and several other things on mine. Some like to use that they can get locally like lithium waterproof axle grease. An oil mix seems to make hte boat run a little faster but needs to be lubed more often. A grease will cling to the cable longer but you may see a little speed loss. I let new cables soak in something like ATF or hydraulic fluid when new but you can also do it between trips to the pond. It helps to get lubrication between the strands.
K&B recommends a 50/50 mix of 20w50 and STP but I've tried that and several other things on mine. Some like to use that they can get locally like lithium waterproof axle grease. An oil mix seems to make hte boat run a little faster but needs to be lubed more often. A grease will cling to the cable longer but you may see a little speed loss. I let new cables soak in something like ATF or hydraulic fluid when new but you can also do it between trips to the pond. It helps to get lubrication between the strands.
#15

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Yeah, just a little more to it than that.
You need to remove the propshaft assembly, that's the thing I was typing about up above with the left-handed threads. You may need ot get in there with needle-nose pliers or hemostats to pull the cable out with. Check it for wear or broken strands of cable while you have it out.
You need to remove the propshaft assembly, that's the thing I was typing about up above with the left-handed threads. You may need ot get in there with needle-nose pliers or hemostats to pull the cable out with. Check it for wear or broken strands of cable while you have it out.
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yeah i kinda ment that i didnt have to take the whole bottom half off. thanks
good new today i ran it, still needs mad tunning but it floats and goes, the only thing i had to buy was a 12v battery lol to run the starter and plug lol
good new today i ran it, still needs mad tunning but it floats and goes, the only thing i had to buy was a 12v battery lol to run the starter and plug lol
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k guys heres a vid of her. sorry the wife was filming and holding out 1 year old and she didnt like it lol
http://www.youtube.com/watch?v=Go9iAvYoX7Q
http://www.youtube.com/watch?v=Go9iAvYoX7Q
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well for the money looks like you did ok, and im sure you already know you need a bigger pond to run that boat in a nice launch and open water it will run nice for ya but be careful with the stop and go and slow running like that as the boat needs to be moving faster than that to force the water up the pick-up to cool it properly, again for the 200 you did good and once on bigger water it will open up and run nice
#20

Have to agree, you need at least 5 to 10X the water you were running in. I could hear it loading up and trying to clear out, not good on any engine. A chase boat would be good as well for "just in case"
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i have bigger lakes and ponds but for starting out and to make sure she floated and ran. thats why im at my little pond. but is it cuz im not fast enough it doesnt start toget on the top of the water?