'95 70hp Evinrude needs Viagra...

[bloody knuckles]

...or an expert guesstimate on what is wrong.

* Won't get past mid-2k rpms @ wot. Reduction in rpms is inversely related to load...heavier the load on board is the lower wot rpms will be...light load = 2700....heavy load = 2200

* S.L.O.W. not sounding off and passes initial self-test when key is turned

* VRO was disconneted after 12 month warranty expired

* New water pump and stat

* New plugs

* New fuel filter

* New fuel

* Compression tested good...think it was 120-125 in all 3 cyl

* Started as in intermittent problem but is now hanging around full-time

* Bulb seems to function correctly. Can pump it up and it will hold the pressure prior to starting. During run it will stay relatively full, but not hard

* Can't find a leak on the visible fuel lines and don't smell gas

* Tested fuel pump on the water, wot, when problem was present, by pumping bulb and listening\watching for change in rpms and\or speed. No change in rpms, no change in speed. But, I'm not convinced it's not the f.pump. A distinct metalic clicking\almost-a-full bang, sound comes from the f.pump and can be felt most strongly on what I think is the VRO pump.


Based on the gremlin bongos in the f.pump I was going to replace it, anyway. However, I'm not sure how to get to the fuel pump without using a cutting torch. Sealoc has a bunch of pretty exploded diagrams showing where each component of the f.pump goes, and apparently they've stolen Harry's magic wand to get the damn thing out because they don't really explain how to remove it.

Any help with the dx and guidance on pump removal would be appreciated.

Thanks

 

[jtexas]

Re: '95 70hp Evinrude needs Viagra...

My theory: she's running on two cylinders.

To avoid a good dose of electro-shock therapy, use an insulated tool or plastic spark plug boot tool (couple bucks at autozone), or else ask somebody ya don't much like to help out.

cylinder drop test:
Engine idling, pull then replace each spark plug wire, one at a time. if RPMs don't drop noticeably, that cylinder's not making power.

If you find a cylinder not working, check for spark:
Remove a plug, reattach it to the boot, hold it against the engine block and look for spark while somebody turns the engine over.

Got spark (or didn't find a cyl goofing off), spark test:
Spark tester (couple bucks at autozone), set the gap at 7/16", look for strong blue spark.

Good spark on bad cylinder, rebuild carbs. Doing all three is only marginally more money and time, don't bother just doing one.

Bad spark on bad cylinder, swap coils - if the the problem follows the coil, replace it. If it doesn't you'll have to troubleshoot the stator & powerpack.

All cylinders hitting with good spark, pursue your fuel pump theory.

let us know how it comes out.

 

[bloody knuckles]

Re: '95 70hp Evinrude needs Viagra...

My theory: she's running on two cylinders.

To avoid a good dose of electro-shock therapy, use an insulated tool or plastic spark plug boot tool (couple bucks at autozone), or else ask somebody ya don't much like to help out.

cylinder drop test:
Engine idling, pull then replace each spark plug wire, one at a time. if RPMs don't drop noticeably, that cylinder's not making power.

If you find a cylinder not working, check for spark:
Remove a plug, reattach it to the boot, hold it against the engine block and look for spark while somebody turns the engine over.

Got spark (or didn't find a cyl goofing off), spark test:
Spark tester (couple bucks at autozone), set the gap at 7/16", look for strong blue spark.

Good spark on bad cylinder, rebuild carbs. Doing all three is only marginally more money and time, don't bother just doing one.

Bad spark on bad cylinder, swap coils - if the the problem follows the coil, replace it. If it doesn't you'll have to troubleshoot the stator & powerpack.

All cylinders hitting with good spark, pursue your fuel pump theory.

let us know how it comes out.

Thanks for the help. I'll give it shot and post the results.

 

[bloody knuckles]

Re: '95 70hp Evinrude needs Viagra...

My theory: she's running on two cylinders.

To avoid a good dose of electro-shock therapy, use an insulated tool or plastic spark plug boot tool (couple bucks at autozone), or else ask somebody ya don't much like to help out.

cylinder drop test:
Engine idling, pull then replace each spark plug wire, one at a time. if RPMs don't drop noticeably, that cylinder's not making power.

If you find a cylinder not working, check for spark:
Remove a plug, reattach it to the boot, hold it against the engine block and look for spark while somebody turns the engine over.

Got spark (or didn't find a cyl goofing off), spark test:
Spark tester (couple bucks at autozone), set the gap at 7/16", look for strong blue spark.

Good spark on bad cylinder, rebuild carbs. Doing all three is only marginally more money and time, don't bother just doing one.

Bad spark on bad cylinder, swap coils - if the the problem follows the coil, replace it. If it doesn't you'll have to troubleshoot the stator & powerpack.

All cylinders hitting with good spark, pursue your fuel pump theory.

let us know how it comes out.

If cyl are numbered from top (#1) to bottom (#3);

All three tested with good spark, however, when wire was pulled individually from #1 & #2 motor died. When pulled on #3 motor kept motoring along. As mentioned, #3 had a good spark. Swapped plugs with #2 just to verify...no change in rpms when wire on #3 was pulled. Also tested as described in first response, no change in rpms. Swapped wires with #2...no change in rpms when #3 wire was pulled, engine died when wire pulled on #2.

So...#1 & #2 seem to be ok with good spark and negative impact on rpms when taken down. #3 has good spark and good compression (previously tested) but not making any discernible power.

Never rebuilt a marine carb and don't want to **** it up. My biggest concern is that it will be a pain in the arse to get the carbs re-calibrated for correct mixture at all rpms...and my early experience with the Sealoc manual have been mixed....sometimes very good, sometime very optimistic in their assumptions. How easy is a rebuild and is it enough of a cost savings to do it myself versus sending it to a shop?

Thanks

 

[chbailey]

Re: '95 70hp Evinrude needs Viagra...

Carbs are easy to rebuild once you get them off. It's getting them off that is the most challenging at times. However, I could think of worse things to work on.

 

[jtexas]

Re: '95 70hp Evinrude needs Viagra...

ya, they're remarkably simple devices, nothing like automotive carbs, you've got I believe only two circuits on that carb - don't be intimidated by the thought of mixture settings on 3 carbs - click over to the "Engine FAQ" section, look for a joe reeves thread titled "Carb Needle Adjustments".

carb kits, about $11 apiece on iboats + couple cans carb cleaner, might take you a few hours your first time - at the shop, it'll be around $95 - $125 each maybe more, not to mention a few weeks without a boat.

Factory shop manual is available at kencook.com or marineengine.com - highly recommended, I also have seloc and agree its ok on some things, just plain wrong on others.

I agree with chbailey, you'll spend more time taking 'em off & putting 'em back on than actually working on 'em.

 

[bloody knuckles]

Re: '95 70hp Evinrude needs Viagra...

ya, they're remarkably simple devices, nothing like automotive carbs, you've got I believe only two circuits on that carb - don't be intimidated by the thought of mixture settings on 3 carbs - click over to the "Engine FAQ" section, look for a joe reeves thread titled "Carb Needle Adjustments".

carb kits, about $11 apiece on iboats + couple cans carb cleaner, might take you a few hours your first time - at the shop, it'll be around $95 - $125 each maybe more, not to mention a few weeks without a boat.

Factory shop manual is available at kencook.com or marineengine.com - highly recommended, I also have seloc and agree its ok on some things, just plain wrong on others.

I agree with chbailey, you'll spend more time taking 'em off & putting 'em back on than actually working on 'em.

Appreciate the help, all, and will probably be back with more questions.

Thanks

 

[bloody knuckles]

Re: '95 70hp Evinrude needs Viagra...

Got the carb's cleaned up and rebuilt and just about everything put back together. Unfortunately work keeps getting in the way and I had to leave the rebuild alone for a couple of days. Now I can't remember how the carb linkage is supposed to go. Looked for nice pictures in the Seloc...no luck. Anybody have a diagram? Specifically looking for something that shows how the linkage rod that connects all three throttle plates together.

Thanks

 

[rickdb1boat]

Re: '95 70hp Evinrude needs Viagra...

This is a 1990 model. Should be basically the same. If you decide to do the fuel pump, remove the starter and air box. That will give you much more room to get to the pump...

 

[bloody knuckles]

Re: '95 70hp Evinrude needs Viagra...

This is a 1990 model. Should be basically the same. If you decide to do the fuel pump, remove the starter and air box. That will give you much more room to get to the pump...

Rick...this is perfect...gotta love modern technology when it works. I'm a little sketchy on what the backside of the connections looks like, though. Not sure if you can get any type of picture in such a tight place, but it would certainly help a brother out...

Thanks,

anotherRick

 

[rickdb1boat]

Re: '95 70hp Evinrude needs Viagra...

This is the only other pic I have. Not real clear. The hook-up should be simple though...

 

[bloody knuckles]

Re: '95 70hp Evinrude needs Viagra...

Thanks Rick. This should help.

 

[bloody knuckles]

Re: '95 70hp Evinrude needs Viagra...

Next project is the fuel pump, I think.

Top cylinder is strong and responds well to throttle movements
Second cylinder is ok and responds but not very well...starts to konck-out but recovers if you back off
Third cyclinder stalls and hesitates when the throttle is opened up, even a little bit. Will die out if you don't back off immediately.

Fuel pump itself makes a clicking noise that's directly related to increased demand\rpm. It's loud and easily felt when you touch the pump. I disconnected the VRO when the warranty ran out and would like to replace the f.pump with a non-VRO as I assume they are less expensive. Any help or recommendations would be appreciated.

Thanks

 

[bloody knuckles]

Re: '95 70hp Evinrude needs Viagra...

Next project is the fuel pump, I think.

Top cylinder is strong and responds well to throttle movements
Second cylinder is ok and responds but not very well...starts to konck-out but recovers if you back off
Third cyclinder stalls and hesitates when the throttle is opened up, even a little bit. Will die out if you don't back off immediately.

Fuel pump itself makes a clicking noise that's directly related to increased demand\rpm. It's loud and easily felt when you touch the pump. I disconnected the VRO when the warranty ran out and would like to replace the f.pump with a non-VRO as I assume they are less expensive. Any help or recommendations would be appreciated.

Thanks

Is it possible to move from the VRO pump to a fuel only?
Cost?
Part number?

Thanks,

Rick

 

[jtexas]

Re: '95 70hp Evinrude needs Viagra...

OMC part# 438559 (superceded 393648) will do the trick. Neighborhood of $80. Might be worth your time to start a thread with the noisy pump issue, just in case there's something else to consider - it's not something I'm familiar with.

I'm kinda curious about how you evaluated the response of the individual cylinders.

 

[rickdb1boat]

Re: '95 70hp Evinrude needs Viagra...

http://forums.iboats.com/showthread.php?t=213623

 

[bloody knuckles]

Re: '95 70hp Evinrude needs Viagra...

OMC part# 438559 (superceded 393648) will do the trick. Neighborhood of $80. Might be worth your time to start a thread with the noisy pump issue, just in case there's something else to consider - it's not something I'm familiar with.

I'm kinda curious about how you evaluated the response of the individual cylinders.

Probably pretty poorly....now that I think about...probably really friggn' poorly!

I'm so stupid...I had the linkage disconnected and gave each cylinder fuel by moving the throttle. My guess is that somebody a LOT smarter than I am designed it so that the carbs would be synchronized.

How badly did I screw things up?

 

[jtexas]

Re: '95 70hp Evinrude needs Viagra...

seriously doubt you screwed anything up.....got the linkages back in place? are the throttle valves parallel, moving together, and ending up horizontal (not beyond) at WOT?

when you advance the throttle, does the CAM hit the ROLLER right on the MARK?

what exactly are your symptoms as of right now?

 

[JustJason]

Re: '95 70hp Evinrude needs Viagra...

check your spark on with a spark board (steven's or equiv, make sure it passes at least a 7/16 gap) just because the plug is sparking when you hold it against the block does not mean its going to spark when its under pressure. your prob may still be in the ignition and you haven't ruled it out yet

 

[JustJason]

Re: '95 70hp Evinrude needs Viagra...

errr.. or if you don't have access to a spark board use a timing light.. or a kv meter (my fav)