my new boat

[1979tarva]

ok heres the deal i got this boat about 1 mounth ago and im tryin to figure out a few things. heres what i have its a 1979 21 foot tarva with a 460 ford and a 12 jg pump and a impeller still aluminum and probably origional. petronix ignition and edelbrock performer intake and holley 750 vac. secondary. timing is around 12 degrees and i dont think its advancing any.
the problem is on the water it will only go 42 mph and at 3000 rpm. isnt this low or is it normal. the secondaries wont even open and today i swaped out the spring in it to the lightest one but havent been to the water yet to see if it works. can anyone help me with this and maybe get me a little tuning info so i can get the boat some help.

[Snorider]

You are right, 3000rpm is way too low for that motor! A stock 460 ford will turn an A impeller (most likely what you have) to about 4500. The intake and carb change should help you out alittle, i would guess 4750rpm if the motor is healthy.
If your timing is not advancing, that is definately a problem, but how are you sure of this? The only way to be sure is to put a light on it. You should be running 35-40 degrees advance at anything above 3000rpm. Try experimenting with the timings more. My motor loves 14-15 degrees base, and 37 full advanced. I could probably go even more, but i havent gotten a chance to try it yet.
Check out the points, see if they are all corroded. Sometimes alittle cleaning out of them helps a great deal.
42mph @ 3000 is doing pretty good. Once you get the motor running properly, i would estimate you have a 55-60mph boat.
[ August 24, 2003, 04:44 PM: Message edited by: Snorider ]

[1979tarva]

the intake and carb were on it when i tested it last and im almost sure the advance isnt working because i took the cap off and tried to turn the rotor by hand and it wouldnt move at all. it has a petronix conversion in the stock distributor so no points to mess with if i cant get anything else out of it im gonna think about the jet drive maybe theres a bad bearing in it.

[1979tarva]

http://www.***boat.com/image_center/data/500/1005boat_3-med.JPG
heres a picture of the boat

[1Bahnerjet]

Here's another pic. of it.
http://www.***boat.com/image_center/data/500/1005boat_3-med.JPG
1979Tarva, this is the kind of Boat I'm looking for, About how much are these type of Boats selling for?
--------
Thats BANNER with an H
[ August 25, 2003, 07:51 AM: Message edited by: 1Bahnerjet ]

[Bryan Rose]

is it me or does 42MPH seem high for only 3000 Rpm's must have a big impellar in it and a really tight pump, especially for a boat that large
Bryan
, I may be wrong here...

[1979tarva]

i payed 2500 for it as it was in that pic it needs some work the interior is coming apart and the paint sucks untill a washed it and polished it

[Bryan Rose]

Looks like a great ride, Hope you get the RPM thing figured out. Are you sure it has an " A " impallar in it?
Bryan

[1Bahnerjet]

1979tarva:
i payed 2500 for it as it was in that pic it needs some work the interior is coming apart and the paint sucks untill a washed it and polished it If the Motors Sound you got a Good deal! Boat has that Spectra Look to it.
--------
Thats BANNER with an H

[1979tarva]

ok i just went out and messed with the boat and i now have it timed at 16 degrees and it advances to 32 i think it will hit 4000 rpm on the trailer tomorrow im going to the lake to see what it will do ill post again to tell you what happens

[Snorider]

1979tarva:
ok i just went out and messed with the boat and i now have it timed at 16 degrees and it advances to 32 i think it will hit 4000 rpm on the trailer tomorrow im going to the lake to see what it will do ill post again to tell you what happens There goes some wear ring clearance eek!
Just because its not a v-drive (or I/O) doesnt mean you can run it on land without problems... Granted, there is no water pump impeller to burn up, but the impeller / bowl area is a metal-on-metal surface which requires water to keep it cool and slippery... Even if you hooked up the garden hose, it wasnt enough water to handle 4000r's. Try not to do that very many more times, or your boat will start cavitating on acceleration - which means you need a pump rebuild. Just tryin to help out.
Oh, and you should be safe with alittle more timing - say 34-35 total, all in by 3000rpm.
-Sno
[ August 30, 2003, 05:52 PM: Message edited by: Snorider ]

[Back Forty]

For reference, mine was doing 43mph(gps) @ 3600 rpm the other day.
Berkley with "A"

[1979tarva]

ok the other things i ended up doing today were new plugs wires msd blaster 2 coil. i understand the thing about the reving without it in the water. i went off of a manual i had at home for the firing order ( ford truck manual from 1973-1979) it seems to run much better but i still cant get any more rpm out of it ive checked everything and the secondarys arent opening on my holley i have the lightest spring in it now i can open them by hand but no change in rpm. i tryed to add more fuel with a can of carb spray to see if that was some of the problem but its not when i tryed to roll the motor over with a wrench today it was extremely hard (worse than my 9.5:1 383 in my camaro) it seems to pop kinda at 4000 rpm and sounds almost like a rev limiter at this point im confused and have tried everything and am about ready to just tear down the whole thing and jetdrive to see if i can just find something thats wrong im curious if a bearing in the jet is locking up but i wouldnt know because i havent had the boat long and havent noticed a drop in rpm but its only been on the water about 4-5 times since i got it.
any ideas would really help

[DansBlown73Nordic]

Do a compression test. You may have a burnt valve. Also you could have a worn cam. This will cause a popping. just a couple ideas.

[1979tarva]

ok after another day messing around i found that where the oil goes in the jet drive there is water mixed with it and its only about half full im not sure how full it needs to be and now im thinking that im gonna re build the drive in the next month or so and hope there is a bearing problem in there or something like that. which way is best to get the drive out pull the motor or try to take it out with the motor in?

[Oldsquirt]

Tarva, it is not terribly unusual to find some water mixed in with the bowl bushing oil. By itself, this should not cause the low rpm problem you are experiencing. Best way to fill is to remove both plugs from top of bowl. Add oil into one side until clean oil starts running out the other...
Before condemning the pump, remove/disconnect the driveshaft and see how well it turns over by hand. Should be pretty easy. Also check to see how easily the engine turns over while it is disconnected from pump.
Perform a compression test!!!!!!!
You might also want to try a different distributor as the electronics in that conversion may be acting up.

[Back Forty]

If your getting 4000 rpm out of the primaries, something must not be to bad off...
Mine had a holley/vaccum secondary carb that was leaning out at WOT and acting the same as you describe. Other than locking out the secondaries because they wouldn't open on their own, I never could get a decent full throttle. I decided not to spend much time on that peticular carb and switched up to a proper Q-jet. Thing is running like a champ now.
Your issue sounds kind of carb related as well.
Wait, I see you said 4000 rpms on the trailer, never mind about the must not be doing so bad thing. May be a carb problem yet.
[ September 01, 2003, 12:38 AM: Message edited by: Back Forty ]

[checkmate76]

I would rebuild the carb. If your secondaries are not opening, I would say that is probably the problem. It is worth a quick and inexpensive try.
rather than tearing into the motor or jet. Do you know how long the boat sat before you bought it?
there is probably old gas that has gummed up inside the carb. idea I would do a compression check too like the other guys advised. and you could disconnect the jet and turn it by hand for a quick check. (re)My bearing was going out last summer...it was a little noisy but never lost any RPM. always start with the easiest and least expensive variables first$.02
[ September 01, 2003, 08:57 AM: Message edited by: checkmate76 ]

[1979tarva]

ok to clarify what everybodys saying the carb is new it first had a 650 carter on it and then i put on the holley because of a stumbling problem on acceleration i can open the secondaries by hand on the holley and no change in rpm also i tryed to open the secodarys and spray carb spray down the carb and it made no difference so im begining to think i have a motor problrm like a bad cam or if what i think could be that i have a pre 71 motor and heads that i dont have valves that are setup for unleaded gas and they are destroyed

[checkmate76]

A compression check would help indicate bad valves or worn camshaft and bad rings. pre-71 should have cast iron heads (you don't need hardened seats if the heads are cast iron).
If the comp check and the carb is good then its either electrical or your not getting enough fuel to the carb.
anybody here can tell you....trying to figure out "what" the problem is can be really frustrating! burningm

[1979tarva]

checkmate i have a 1978 bronco that has pre 71 heads (non smog) because of the fact thet they were so old they werent setup for unleaded fuels and the seats were destroyed so i ended up with about 500 in machine work to repair them so they could be used again.