Sediment in Carbs??

[HS91_Mike]

I have a 97 Johnson 175 OR. Have had some problems with fuel system. Removed all fuel in tank, replaced fuel lines and fittings and had the carbs rebuilt. The mechanic told me that there was Black carbon-like sediment in the the carbs. The pieces were large so they must be accumulating and binding after they enter the carbs. Cant figure out how they got passed the screen at the uptake or the filter above the fuel pump. Any ideas on what this is and how to prevent it?

If it was an inert sediment, then worse case scenario, it should get trapped at the filter. Right??

 

[coolguy147]

Re: Sediment in Carbs??

replace ur filter it may be full and letting the bad things through

 

[HS91_Mike]

Re: Sediment in Carbs??

The filter was clean. There was a lot of water/varnish in the fuel/water separator, which was replaced along with fuel lines and fittings. The fuel pump was also replaced.

 

[tx1961whaler]

Re: Sediment in Carbs??

The black gunk may have been from your old fuel lines. Ethanol turns some of them to goo. The new fuel lines should solve your problem, if you replaced the ones on your engine.

 

[Faztbullet]

Re: Sediment in Carbs??

Replace what few rubber lines there is on this model and replace the diaphrams in vro. I have had 3 V-4's and 2 V-6's this year for same problem. The debris would hang under needle and cause carbs to flood sometimes. 4 of the 5 was the fuel diaphram in vro was degraded and rubber was cracked and falling off in small pieces. The air motor diaphragm kit is part number 435921 ($36)and the fuel pump repair kit is 436095.($44).I suggest you replace both.

 

[tashasdaddy]

Re: Sediment in Carbs??

replace all your fuel lines (tank to carbs) with alcohol resistant lines. Ethanol softens the old lines, the interior starts to sluff off, and gets into the carb bowls, settling to the bottom, and then clogging ports especially the high speed jets.

 

[freddyray21]

Re: Sediment in Carbs??

agree sounds like the lines and possibly fuel pump or vro diaphragm.

 

[HS91_Mike]

Re: Sediment in Carbs??

Thanks for the help. The uptakes were not replaced. The fuel lines from tank to carbs were as well as the fuel pump. The VRO diaghram in the VRO pump was not. Or is the VRO pump the same as the fuel pump? Also, right above the fuel pmp there is a reservoir. I assume that these particles will accumulate here as well?

 

[Faztbullet]

Re: Sediment in Carbs??

If the filter has these particles do as Td suggests as problem is from filter to boat. If no particles in filter its the Vro/fuel pump or hose to carbs. Replace the hose feeding carbs as rest is the hard plastic style.

 

[tashasdaddy]

Re: Sediment in Carbs??

you also may need to install a fuel/water separator filter.