New 2.4l "frankenmotor" tach help

[Partonjoshua]

Just purchased a fresh rebuilt 2.4l, runs like a brand new motor, but today my tach just stopped working. After looking at it it looks like the signal wire is connected directly to the yellow wire on the stator. The stator was replaced when i picked up the motor last week. I immediatly thought the voltage regulator went bad, but when i looked at it the voltage regulators are not even hooked up and all the wires are cut off of them. Is this common, low amp charging system maybe? Motor still charges the battery. Not sure what motor i even have to be able to order parts, serial number on clamp says its a 2.0l, number on freeze plug says 1990 xr4, cowl says mariner 200hp, has wmv carbs. So looks like it was pieced together from several different outboards. Do you guys know of a way to test the tach to see if the guage just crapped out or if it is an issue on the motor side?

 

[Dukedog]

use tha block number mostly.. tha wmv's were available on tha '91 up motors.. could be late '90 build.. pic of port side of block would tell tha tell.. carbs have a number stamped on tha starboard side of tha casting, by tha plate shaft.. should be wmv-xx-1, 2, 3 top to bottom.. you said regulators?.. tach going to yellow on rectifier?.. is rectifier mounted jus above tha switch boxes?

cowl number along with clamp number can't be trusted as good number with tha age of it much....

 

[Partonjoshua]

Yes looks like a rectifier mounted above switch boxes that has tach wire attached to, but also has the two square regulators under the coil plate with all the wires cut off them. The starboard side of the carbs do not have any numbers on them but the top says wmv. Took a few pics. Looks like the small box above the switch boxes is melted so im assuming thats the culprit with the tach. Trying to get a few pics.

 

[Dukedog]

sorry, meant port side of carbs.. wmv's are tha latest and last version of tha V6 carb.. like '96/'97 up best I remember... has been changed to 16 amp 'lectrics somewhere along tha line. tha TWO reg/rec 40 amp stuff started in '92.. '89 ta '91 had one big water cooled reg/rectifier.. sounds like a melted rectifier?.. no tach results..

yep, sounds like a Heinz...

 

[Partonjoshua]

Thanks for clearing up the regulator deal, just ordered a new cdi rectifier, saw some generic ones for about 12 bucks, but dont know if i would trust those. How prone are these to going out? Is an onboard spare a good idea?

 

[Dukedog]

pretty dependable far as i'm concerned.. 99% of my motors (had many, way more than most,, all V6 mercs) had either 9 or 16 amp stuff and don't remember a ever havin' a bad one (rectifier)....

 

[Partonjoshua]

Ok thanks ill just order one, will give an update when it comes in.

 

[Faztbullet]

Does the flywheel have 8 bolts around edge or is it smooth 1 piece?

 

[Partonjoshua]

Flywheel has 8 bolts around the edge and 8 bolts in the center.

 

[Partonjoshua]

Quick update, replaced the rectifier and the tach now works, thanks for the help Dukedog.