an update on my 120 force 1990 motor troubles

[Kajun37]

well..after going through 3 mechanics and still no working engine..i decided to try to fix it on my own using a manual and asking you guys for help....well..2 mechanics said i had a bad power pack so i found a used powerpack and ignition coil set on ebay.....when it came in i used my cylmer manual and changed out one of the packs...dropped it in water.. it sounded much better..but it was still dieing out....i think i fixed the spark/power pack problem but i believe i have a fuel problem still.<br /><br />some pics for your viewing pleasure packs and coils completely off!!then finished product ..i was proud of myself lol<br /><br /><br />

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<br /><br />so..i came home and pulled the fuel pump to check and see if this one mechanic had rebuilt my fuel pump like he said he did and low and behold...he did NOT change one single thing on my pump..same gaskets and old diaphram...not only that he had the screen on BACKWARDS...here is a picture of the "NEW" diaphram he installed a couple weeks ago...stretched and not pliable...oh yea..he wants to charge me $40 + 2hrs of labor for rebuilding my fuel pump..it will be a cold day in hell before he gets paid.<br />

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<br /><br />so..now i need to rebuild my fuel pump...and while i'm at it i want to rebuild my carbs.....where is cheapest place to get these complete kits?..also i have never done this before lol<br /><br />i have bought and compression tester and a spark tester.....but i'm not sure how to use this stuff...someone told me i have to ground each spark plug to engine or i'm gonna fry more power packs.. so i'm scared to do it now......can i just pull one plug at a time and test it.. and leave the others in and plugged? or do i have to pull each plug and clip a ground wire to each coil wire to engine?<br /><br />also is there a way to do this with one person?i dont have anyone to come help me since i work late hours.<br /><br />next is compression check...can i check one cylinder at a time with me at center console... then when i'm done go back and check compression gauge? or will it not hold the test on gauge? or do i really need 2 people to do this?..can i check it cold?..because my engine wont run long enought to get warm <br /><br />what is the best way to flush out a fuel tank without tearing apart my boats flooring and CC to get it out?<br /><br />and last question...how do i know which kit and what type of carbs i have..tolson or walbro?

 

[jaba]

Re: an update on my 120 force 1990 motor troubles

Hi Kajun,<br /><br />A few things I can answer cause I´ve tried them on my Force project. Siphon was the easiest way for ne to empty the tank. So, find a hose or tube long enough to go from the tank to some can on the floor. It is important that the other end of the hose is lower than the tank in your boat. I used a hose approx 5/8" dia. Place the tube in your tank and suck so that the fuel starts flowing to the can. Be sure the hose in tank stays at the bottom of the tank, so you will get all the bad fuel out of it. Be very careful not to spill the fuel to floor and places you don´t want it to be, and it really doesn´t taste good.. When you get it out, please take it to some place they get rid of it ecologically, thanks.<br /><br />I´m sure you can measure the compression by yourself. It depends on what kind of meter you bought. Is your meter intented to screw to plughole or is it a version that has a cone at the measuring end? I suppose you can use the one with screw thread without help. I advise you to contact to the shop you bought the meter from.<br /><br />The make of my carbs (120hp 1992) was mentioned in cast, if I remember correctly it was tillotson.<br /><br />Hope you find my post usefull,<br /><br />-Jaba-

 

[eurolarva]

Re: an update on my 120 force 1990 motor troubles

Fuel pump here and carb kit here. When you do the fuel pump discard the small oring type gaskets. They are for the fuel valves and they probably wont fit. Two of the fuel valves are press fit and hard to remove without damaging them however they are only 5 bucks a piece and the correct gaskets for them are half a buck each.

 

[Kajun37]

Re: an update on my 120 force 1990 motor troubles

thanks jaba and euro....where can i find those fuel valves and correct gaskets? i'd like to replace anything ic an just to be sure it works good...also is there a way to tell which carbs i have?

 

[eurolarva]

Re: an update on my 120 force 1990 motor troubles

You will have to get them from mercury valve part number is 21-F177330 and the gasket is 27-F84792. You will need 3 of each. Yours probably has a brass center valve held in place by a screw. The brass is no longer made however the part above will work in all three positions. Last time I tried the gaskets that come with the rebuild kit did not fit. Maybe they have fixed this. You can test it by using one of the gaskets from the rebuild kit in the fuel float that is held in place by the screw. The gasket needs to fit around the spring side of the fuel valve. When I tried this with the rebuild kit gaskets I tore the gaskets because they were the wrong size. The part number listed above works the way they are suppose to.

 

[Kajun37]

Re: an update on my 120 force 1990 motor troubles

great i will get those valves/gaskets on order tommorow...is there anything else i should do to the carbs before rebuild..like soaking them in decarb or something?

 

[eurolarva]

Re: an update on my 120 force 1990 motor troubles

Spray carb cleaner is pretty weak and should be okay. You do not want to use too strong of a cleaner because it will eat through the protective coating on the carburator. Another product that works well is contact cleaner. I dont think decarb spray will do any good. Spray them down, go through the passages with a thin wire then let sit. Spray again repeat the wire and use compressed air. Keep the air pressure below 30 psi if possible. Only do one carb at a time and do not reverse parts from carb 1 to carb 2<br /><br />Two of the valves on the fuel pump are press fit. Be very careful removing them as to not damage the other parts of the fuel pump. I used a deep socket to put the new ones in. Seems to me one of them is set up so it is impossibe to get it out without breaking it. You have to pound from the spring side.

 

[Kajun37]

Re: an update on my 120 force 1990 motor troubles

update from today...<br /><br />well i finally was able to do a compression check and a spark test by myself thanks to a long piece of pvc pipe.<br /><br />here are my compression readings..these are taken cold..motor hasnt been started in a week.<br /><br />#1. 137<br />#2. 120<br />#3. 140<br />#4. 133<br /><br />lil low on #2 huh?..maybe a decarb when i get it running will bring it back up?<br /><br />spark test.....after switching out the #3& 4 power pack last week..i thought i had fixed my electrical problem...cuz it sounded great when i started it last week....but tonight when i did the spark test...#4 ign coil wire had NO spark....so i switched the #4 wire that goes to the power pack with the #3.....and spark came back to the #4 ign coil wire.....bad power pack again?...this would be the second one i change...even though i never tested the old one..was just going off what mechanic's told me..that my #3 ign coil had no spark.<br /><br />so tonight i guess i'll swap out the power pack again...if that dont work...then i'm guessing it has to be the stator?<br /><br />my stator part # that is on it is FCC 3007c<br /><br /><br />recieved my fuel pump and carb rebuild kits today from iboats..so i'll be working on that also this weekend...guess i have some work to do <br /><br />any more troubleshooting tips for the electrical system?...where could i find a DVA adapter in a local store?home depot?walmart?

 

[eurolarva]

Re: an update on my 120 force 1990 motor troubles

I have seen them on the the internet for 35 bucks. We are not allowed to post links anymore. Just do a google on DVA Adapters.

 

[Kajun37]

Re: an update on my 120 force 1990 motor troubles

nah dont want to order online, takes too long...need it tommorow..was wanting to know what store should have them.

 

[eurolarva]

Re: an update on my 120 force 1990 motor troubles

Some marine parts places might sell them. I have seen reference on the internet to building one for less then 20 dollars but cant find scematics or build prints for one.

 

[Kajun37]

Re: an update on my 120 force 1990 motor troubles

euro..i recieved the carbs kits and when i took them apart...hardly anything from that kit was useable....the big gasket was...the bowl gasket was...and the spring..the other the parts in the kit were nowhere to be found on my carb..the needle might be able to be used it was 4 sided...my needle is 3 sided...i have the TC-106A and TC-107A carbs...maybe i ordered the wrong one?

 

[eurolarva]

Re: an update on my 120 force 1990 motor troubles

That carb kit is a generic kit. I dont know if this link will last but it mentions the Tilltson TC carb as being the correct kit.<br /> http://www.maxrules.com/fixforcecarb.html

 

[Kajun37]

Re: an update on my 120 force 1990 motor troubles

hmmm..well dang..i guess i wont be rebuilding my carbs if this is the only kit available......my carbs were pretty clean..no varnish or sludge anywhere..was surprised..i just cleaned them out real good and put them back together..used a spray can of carb cleaner on each carb lol

 

[eurolarva]

Re: an update on my 120 force 1990 motor troubles

Try going to the mercury site and see what carb parts they show for your motor. You might be able to find what you need there.

 

[Kajun37]

Re: an update on my 120 force 1990 motor troubles

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