Need wiring diagram for 88' Thompson Carerra 200 with mercruiser 3.7l

[Hardypanchal]

Hello my fellow sun loving folks at Iboats!
Im an ASE cert Automechanic and enjoy small electronics as a hobby and have all the proper tools to solder and heatshrink everything.
I have ZERO experience with carbd engines so
I need lots of help with this boat.
Its a 1988 Thompson Carerra 200 with a Mercruiser 3.7l in it. Its an inboard motor with a stern drive. First of all, the ignition cylinder is missing.
Someone please help me find all the wiring diagrams for the control panel (ignition, starter, guages, generator, and more)
I also found out that the oil smells like gas and has small amounts of water droplets in it. Boat has been sitting for 2yrs now, rain, sleet, snow, everything without a cover in newhampshire weather.

 

[tpenfield]

:welcome: to iBoats . . .

Boats are not well documented, particularly brands that are out of business. So it is not likely that anything exists for the boat itself.

Most of the wiring is related to the engines, which are fairly well documented. See if you can get the service manual for the engine (you will need to get the engine serial number as reference). They will have wiring diagrams with wire color codes to help you sort out the wiring as needed.

Change the oil and see if it maintains itself or becomes contaminated again from running, etc.

 

[Scott Danforth]

Hello my fellow sun loving folks at Iboats!
Im an ASE cert Automechanic and enjoy small electronics as a hobby and have all the proper tools to solder and heatshrink everything.
I have ZERO experience with carbd engines so
I need lots of help with this boat.
Its a 1988 Thompson Carerra 200 with a Mercruiser 3.7l in it. Its an inboard motor with a stern drive. First of all, the ignition cylinder is missing.
Someone please help me find all the wiring diagrams for the control panel (ignition, starter, guages, generator, and more)
I also found out that the oil smells like gas and has small amounts of water droplets in it. Boat has been sitting for 2yrs now, rain, sleet, snow, everything without a cover in newhampshire weather.

the boat has points, an ASE mechanic can figure that out as that is the first thing they teach mechanics in trade school. and I believe that all mechanics call that the coil

the factory service manual for the motor has all the wiring you will need, the remainer (lighting and bilge) are covered with the standardized wiring in the stickies.

you can buy a manual here https://publications.brunswick.com/
or you can view a manual here http://boatinfo.no/lib/library.html#

the fuel in the oil is most likely a ruptured diaphragm on the fuel pump, either get a rebuild or get a new one. get a mechanical pump, dont try to "upgrade"

start reading up on the 470 motor. as far as motors go, you will need to look at nearly everything.

does it have the updated HX
is the cam seal to the waterpump intact, or has that failed
has the head gasket went?

there are plenty of write-ups in the forums

make sure you do all the outdrive service work

new raw water impeller
inspect the u-joints
inspect the gimble bearing
inspect the alignment
change the gear oil

and then inspect the hull. any boat old enough to have a 470 will most likely have rot starting in the transom and stringers.

since your boat is a 1988, its 33 years old. that is double the design life of a boat. so expect to have a few projects prior to getting the boat in the water.

 

[Hardypanchal]

So today i sucked out about 4gallons of water(perfectly clear) from the oil dipstick tube, aparently the previous owner had already taken out all the oil. How did this water get in there? the engine still had the oil fill plug seated well on the valvecover and the dipstick was in its place the whole time with the wooden cushion engine doghouse over the engine. The engine also was emptied of all fluids before the boat was given to me 2yrs ago and its been sitting around my yard ever since. Has anybody ever come across this?

 

[Scott Danforth]

the block full of water vs your oil smells like gas in post one?

if there was no oil in the block and it was full of water, my guess is the rings, bearings and crank are not in good shape.

4 gallons would have filled the entire crank case up to the top of the combustion chambers.

was the boat sunk in its past, if so, every system needs to be gone thru. wiring harness needs to be changed, steering cable will be rusty, etc.

If it was me, I would have the drive off, then yank the motor out and go thru it as an inspection at a minimum. if the motor is toast, you can bolt in a 4.3 for not much work.

 

[Hardypanchal]

So today i sucked out about 4gallons of water(perfectly clear) from the oil dipstick tube, aparently the previous owner had already taken out all the oil. How did this water get in there? the engine still had the oil fill plug seated well on the valvecover and the dipstick was in its place the whole time with the wooden cushion engine doghouse over the engine. The engine also was emptied of all fluids before the boat was given to me 2yrs ago and its been sitting around my yard ever since. Has anybody ever come across this?

 

[Hardypanchal]

So compression test the cylinders? 180psi each with sparkplugs out? Im not trying to yank the motor out unless i know its junk! Seems like a lot of work (seeing that i dont have an engine hoist tall enough to reach in the boat on the trailer) when i could just compression test it right?

 

[achris]

The crankcase has been full of water, all the way to the top. Crankshaft, rods, camshaft have been sitting in that water. What condition so you think they'll be in? You might get good compressions, but that's only testing rings and valve seats. Fire that engine up and it'll tear itself to pieces very quickly.

Chris....

 

[Bt Doctur]

Hope it was a free boat. the motor is finished

 

[Scott Danforth]

So compression test the cylinders? 180psi each with sparkplugs out? Im not trying to yank the motor out unless i know its junk! Seems like a lot of work (seeing that i dont have an engine hoist tall enough to reach in the boat on the trailer) when i could just compression test it right?

180 psi indicates either you have a bad gauge or you have water or oil in the chambers. 150 psi is the cranking PSI spec from mercruiser on a new motor

pull the wheels on the trailer, run the hubs on the ground and you should be able to pull the motor with your hoist

 

[Hardypanchal]

I did a comp test, comes out to 145. Now the coil, i have batt voltage on both sides of the coil with key on, is that correct? doesnt seem to spark, i pulled the coil wire from the distributor cap and brought it close to ground but no spark while cranking... i even bought a new coil, still tests battery voltage on both +&- terminals. she's almost ready to fire up! it needs fire! lol

 

[Bondo]

i have batt voltage on both sides of the coil with key on, is that correct? doesnt seem to spark,

Ayuh,..... The points are what fires the coil,.....

 

[Hardypanchal]

Can I put the coil output secondary wire within arcing distance of any ground and see the arc jump when im are cranking the starter?

 

[achris]

12 volts on either side of the coil is correct ONLY if the points are open. If you turn the engine until the points are closed, then you should see about 7-8v on the + and 0v on the minus.

Better than holding the lead close to ground, find an old spark plug and put that in the lead adn lay it on the engine block. Should see a nice fat blue spark.

Chris......

 

[Hardypanchal]

Gr8 suggestion to check spark Chris! got the spark, and the motor starts on starter fluid.
But theres no fuel goin into the carb, but when i take the hardline off of the carb and suck fuel out, i can see the inline filter fill up(aftermarket auto fuel filter in the middle of the hardline between pump and carb). Why wont it pump out fuel when the engine turns? i can get it running on starter fluid

 

[achris]

Automotive filters have no place in a boat! Quickest way to end the day badly.

Remove the hard pipe, remove the 'non marine' filter. Throw now useless hard pipe and filter in the rubbish bin. Buy new hard pipe and fit. Buy genuine Merc spin-on water separating fuel filter kit and install that in the flexible line between the tank and the engine fuel pump.

Why no fuel? Probably a failed fuel pump...

Chris....

 

[Hardypanchal]

I dont have availability of marine parts, i was wondering if someone could post how many gph and psi the carter mechanical fuel pump is rated for? id like to replace it with an electric fuel pump upgrade so i dont have these diaphram problems on the water

 

[nola mike]

The mechanical fuel pumps are pretty reliable. You should stick with it. Going electrical is going to be more work, more expensive, probably less reliable. And it needs to be a marine rated pump anyways.

 

[achris]

I dont have availability of marine parts,...

Putting anything but marine rated fuel and electrical parts in a boat is a quick way to either the next life, or a law suite so big you'll wish you were heading for the next life.

If you can't get marine parts, stop working on boats!

If you wish to change the mechanical pump to electric, you will also need an oil pressure switch (marine rated) and a relay (marine rated) and the knowledge of how to connect them all up safely. Stick with the mechanical pump, use an online MARINE parts store. Here's a suggestion, use the iboats store. The website you are currently on.

If you don't understand what the difference between automotive and marine parts is, and why we say using automotive parts in a boat is such a bad idea, despite the parts looking the same, read this. -> https://forums.iboats.com/forum/engi...omotive-engine

Chris....