Changed Water Pump Now Motor Surging?

HOU-CHAP

Seaman Apprentice
Joined
Nov 21, 2004
Messages
34
All,<br />Once again I am hoping yall will be able to help me out in a pinch. First things first, I have a 1977 V-4 Johnson 140. Changed the water pump over the weekend because I was getting an alarm at WOT, and finally wanted to try and correct it. Changed the water pump using a kit which included all the seals, orings, housing, plate, etc... Finally got the splined shaft stabbed, bolted it back up, reconnected the shift linkage and fired it up. It fired right up, but now is surging at idle? To disconnect the shifting linkage I unbolted what looks to be something for the choke (some sort of vacumm valve?) to move it out of the way to make room to loosen the big bolt on the shift linkage. I disconnected both cables also to make room to disconnet the linkage on the shift rod. I have done a bunch of searches about surging, but haven't see any fixes that involve something I could have changed doing the water pump :confused: The motor has run perfect the last couple weeks, except for an alarm at WOT from time to time (I have just been keeping it under 4700-4800rpm). It is not a "hard" up and down idle surge, but it revs up then revs down (fairly quickly). I have not had it on the water yet (just the muffs). I am bummed out because I had plans of fishing all over my three day weekend coming up. I am now wondering if that is going to happen :( . I am hoping someone has a miracle fix like I have gotten so many times on this site. FYI the boat is not here, so I am unable to try anyhting and reply. Hoping more for someone to say "oh i did that once this is the problem..." or things to look at when I get down there again this weekend. The motor has not overheated, I replaced the coils and power pack about a month ago, cleaned both carbs per the site "standards" a couple weeks ago, and installed a water/fuel seperator about a month ago. It has run fine though up until doing the water pump. Thanks again guys for any help you can provide..<br /><br />Sorry so lengthy just wanted to try to build the best picture possible on what it is doing.. Thx again!
 

HOU-CHAP

Seaman Apprentice
Joined
Nov 21, 2004
Messages
34
Re: Changed Water Pump Now Motor Surging?

Anybody have any idea's on what would cause a motor to start surging at idle after changing a water pump? 1977 V-4 140.
 

ezeke

Supreme Mariner
Joined
Sep 19, 2003
Messages
12,532
Re: Changed Water Pump Now Motor Surging?

Did you put the exhaust seal back? See part 71 on the "exhaust housing" diagram in the BRP parts diagrams for your model.<br /><br /> BRP Parts Diagrams <br /><br />Without the seal, exhaust fumes can leak into the housing and back to the motor.<br /><br />The easiest way to check is to run the motor with the cover off and see if it still surges.
 

HOU-CHAP

Seaman Apprentice
Joined
Nov 21, 2004
Messages
34
Re: Changed Water Pump Now Motor Surging?

ezeke,<br />Thank you for taking the time to respond. I did not disturb the exhaust seal, because I did not have one in my kit to replace it with. When I was running it on the muffs, the hood was off it. I guess it is possible it could have been damaged upon reassembly of the LU. I am wanting to check everything on the topside before dropping the LU again. Stabbing that driveshaft spline is a PITA by yourself.
 

ezeke

Supreme Mariner
Joined
Sep 19, 2003
Messages
12,532
Re: Changed Water Pump Now Motor Surging?

That seal goes between the mid section and lower unit so you can usually see it by dropping the unit down a little, just to make sure its still seated properly. <br /><br />I don't know what else would cause that, but surging is often starving - improper fuel/air mix. BTW, Did you reconnect that hose that runs under the carburetors?
 

HOU-CHAP

Seaman Apprentice
Joined
Nov 21, 2004
Messages
34
Re: Changed Water Pump Now Motor Surging?

I will take a look at the exhaust seal if I can't find anything topside. I tried to be aware of not messing up the seals on the exhaust or water tube when I was stabbing the LU back on, but I guess I could have pinched something (that dam things heavy!! :) ). The surging to me felt like a fuel restriction issue too. Ran great weekend before last, then I changed the water pump and now this. I didn't have any time to spend messing with it last weekend, but I will fiddle with it this weekend. Just was looking for some usual suspects to look out for. Thx again for your help!
 
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