Home › Forums › Bass Cat Boats › Oil / Temp Horn Going off at Wide Open Throttle , Fully Trimmed / How move jackplate?
oldtimer57.
Help! I am trying to get out of town to go fish the STREN event at Kentucky, but having boat troubles. 2005 Pantera Classic, 2007 200 Opti, 27p tempest When running at WOT, fully trimmed, turning 5250 – 5300 rpms, my horn goes off (constant) after about a mile or two of running. Guardian kicks in and backs me down to 4900 rpms. If I back off, it will quit, and I can run all day long with no problem as long as I dont open it all the way up. Also, I can run WOT with the trim down and it will run fine, but I guess its because my rpms are backed down when I do that. I have not moved the jackplate, or for that matter done anything that would cause this. I put in a new water pump and a new thermostat, but same problem still exists. I took it to have it worked on and the computer said that the faults were with the cooling system I think. They said it was only getting 3 -4 pounds of water pressure, or at least that is what the computer says. I do not have a water pressure guage so I cant tell on my own. I am thinking about moving the jackplate down some to see if this fixes problem. It sort of looks like the jackplate is higher than I remember in the past, but I have never really payed much attention. Also, the 4 bolts that hold jackplate in place are tighter than tight and I couldnt possibly imagine it moved any, but I guess anything is possible. Do you think this is the problem? I hate to move it down any, because the current setup absolutely screams. 74.9 on GPS ! If I move jackplate down, (Slidemaster Jackplate from BCB) How Far? Do you just lossen the 4 bolts? Will it fall on my feet? Does the big bolt on the top work as a height adjustment? Do you need to take the 4 bolts all the way out? Or am I wasting my time and this probably isnt the problem? Thanks, Travis Fox
Loosen the two bolts on each side of the plate, and turn the center bolt counter clockwise to lower the engine. You may have to shake the engine a tad to move, or trim up to a more nuetral position where the weight of the engine is more centered on the transom while moving. ? Lower 1/2 ” or so and see if it helps. D. After re-reading youre post i would check the poppit (?) valve to make sure it wasnt trashed up(open), and also a ?, Did you repalce both thermostats ? I dont think youre too high with the 200 Opti, but rather one of the thermostats is open with thrash, or poppit is stuck. I take it you dont have a temperature gauge / smartcraft ?Last edited by dbasketman on July 16th, 2008, 7:56 pm, edited 1 time in total.
also try backing off the trim. No boat needs full up trim, especially BCB hot-rods like the classic. Running the propshaft at an angle to the surface of the water is less efficient, and tends to aerate the water going into the intakes on the side of the gearcase causing low water pressure. Are you maintaining at least 10-12 PSIG at WOT??? Anything lower will start to heat up #1 cylinder as it is the high-point on the water jacket.2008 Pantera Classic2014 Mercury Pro XS 200
Thanks for the advice guys. Maybe for this tournament and practice, Ill just run with it trimmed down some and not at peak. Do you think I am going to hurt anything as long as I dont get the horn? WHat is a Poppit valve? I had a similar issue with a 3.0 L EFI once on the same boat and it was some valve that had to deal with oil pumping into the reservoir. But I dont know if it is that because like I said, the horn will go off and not come back on unless you have it trimmed all the way at WOT. Plus the fault reading was water pressure. THey just told me they replaced the thermostat. I dont know if they did one or both? I guess I need to check and get back to you. Surely they would have done both. I dont have a temp guage, water guage, smart craft etc.., just the basics for this poor arkie
Just wanted to let you know, it must have been the Jackplate. I got up close and looked and it seemed as if there was a slight mark where it use to be, so I lowered it about 1/2 inch to that mark. Ran 2 tanks of gas wide open so far this week and it hasnt gone off again. Dont ask how it must have moved up, but problem fixed.
the poppet valve is used to fill the cylinder block water jacket with water. If water could just run out of the block, at idle the top of the block would be empty and youd burn the top cylinder(s) on each bank. The poppet valve is just a fairly lightly sprung check valve that lets water out, but only if it is under pressure, so that the modest water flow from the pump at idle will still fill the block and cool everything. The risk is getting one stuck open due to a piece of trash, as that will drain the block at low speeds and overhead the upper cylinders. Thermostats rarely stick closed, but do get blocked open with trash, and that makes the motor run too cool, something you want to avoid at todays tighter internal tolerances…2008 Pantera Classic2014 Mercury Pro XS 200
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