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1975 Evinrude 85hp Low Compression!? Not Running

Fishhawk-----Sorry , but crankcase compression and cylinder compression are totally different.------Crankcase compression does not have anywhere near 60 PSI !!!
 
I know what the sealing rings are I just never heard them called crank rings before. Fishhawk90 you need to start your own post on your motor. You have issues that are far beyond anything a VRO can cause and it sounds like.you need some guidance on your motor.This post has gone.far beyond the OPs original question.
 
racerone said:
Fishhawk-----Sorry , but crankcase compression and cylinder compression are totally different.------Crankcase compression does not have anywhere near 60 PSI !!!
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then why would those check valves be in each case if it was not a high amount of pressure? how much pressure 15 psi u think would go through those thin hose ? also have u taken apart a vro & see how strong the force of the spring is & the inch of vacuum is required to move it?
 
Sure I have taken VRO pumps apart !-----Why would you think the VRO is so big ??----Is that because more square inches are needed to compress the spring.-----I suggest you do some more study on the bleed system and the general operating conditions of a V-4 outboard motor !!----And there is not much vacuum created in a crankcase because the reed valves open !
 
Excellent article Mr. Scott. Thank you. Notice the newer models are alcohol "resistant". Not to be taken as alcohol "proof". However, you have educated me and I appreciate that. I also noted that earlier VRO's had a broader mixing ratio.....up to 150:1 at idle. Then I wonder why those ratios were adjusted closer to 70 or 80 to 1? Is 150:1 too lean? Take care, Tim
 
The fully functional original VRO I just took off of my 88 70 hp was 30 yrs old good enough for me. OMC increased the oil ratio because of storage problems. Same issues they had with the 100-1 mixes they tried in the mid 80s. It wasnt a running problem it was a problem when the motors sat for any length of time.
 
Right okay, that makes sense, there isn't enough residual oil for off season. So owners should fog before storage. That way bearings get protection too. Adding oil just to cylinders, would not help the bearings much, or were storage problems limited to cylinders, rings and pistons? For many years, I limited my repairs to smaller size motors because I had a shop at my home right in town and rarely worked on bigger boats and hence VRO's. So many that I repair now have been tampered with and/or disconnected. I like the variable ratio idea and the system is so much more precise than the early oil injections based on throttle position only......like my 1969 Yamaha DTI enduro.
 
timguy said:
Right okay, that makes sense, there isn't enough residual oil for off season. So owners should fog before storage. That way bearings get protection too. Adding oil just to cylinders, would not help the bearings much, or were storage problems limited to cylinders, rings and pistons? For many years, I limited my repairs to smaller size motors because I had a shop at my home right in town and rarely worked on bigger boats and hence VRO's. So many that I repair now have been tampered with and/or disconnected. I like the variable ratio idea and the system is so much more precise than the early oil injections based on throttle position only......like my 1969 Yamaha DTI enduro.
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The Yamaha system is much better than the Vro system. In the top 2 all time great oil injection systems. Suzuki being the other one.
 
Not sure where the rust shows up, but if it's in the cylinder sleeve, the more nickel content. The more corrosion resistance. Since nickel, of course, is expensive, perhaps some manufacturers will run a lower percentage, anticipating that since oil is mixed with the fuel, that the cylinder sleeve is pretty safe. Higher end cast may run up to 30, even 35 percent nickel, but since sleeves are so thin, I might suspect that it wouldn't be a huge difference in cost. Considering solid cast engine blocks, like the early Suzuki outboards, nickel percentage is going to be a huge consideration. I have a 16 Spirit, it is heavy, but I love it, effectively using centrifugal advance. I run 100 to 1 Amsoil, which, of course, has even poorer rust inhibiting properties than petrol based oils. Have had no problems over winter storage up in remote NW Ontario, in an unheated shed with several other motors.
So to summarize, I really believe that your better cast iron recipe will include higher amounts of nickel and perhaps that's where the Japanese get the edge. The Philippines produces lots of nickel and the production costs are way less than the US. A large amount of nickel is exported to Japan, and it could well be that the cheaper cost to the Japanese to acquire nickel, makes way for an opportunity to produce a better overall cast iron for the same money when competing in the US market.
 
racerone said:
So how do the smaller Yamaha motors that run at 100:1 deal with long periods of storage ??
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The only issue I see with Johnson/Evinrude engines sitting is the amount of oil pushed/left in the carbs when the fuel evaporates.

The only issue I have seen in smaller Yamaha engines , is clogged idle jets from evaporated fuel, especially if extra additives were mixed in the fuel tank.
 
A fellow mechanic (technicians weren't born yet), many years ago, once said to me while working on a fairly new 1968 Chevrolet that was equipped with air conditioning... "Sophistication Breeds Problems!"... and that saying jumps foremost to my mind quite often. Really makes me wonder if we were better off back in 1955 or 1960 pertaining to the boating world... magneto and mechanical shift, perhaps an electric starter was as sophisticated as we got and that worked very well for us.

Then as the years slowly dragged by... up popped the highly complex battery charging generator system, automotive ignition for God's sake, electric shift... and as we squeezed into the late 1960's... battery powered electronic ignition hit the scene to drive us nuts. Then, as we entered the 1970's and only three years barely drug by to 1973, self powered similar to the old magneto system came into being, a solid state ignition system of which has not been surpassed as of the present time and is apparently the ultimate as we now recognize the word ultimate.

Then, as another decade dawned, barely..... up, raising its ugly head, the VRO came into sight as of 1984! (sigh)

Yeah.... Many of us understand every bit of the sophistication forced upon us and handle it well, making an honest living by treating the customers fairly. But then there are the other "technicians" who have no idea what they're doing, or perhaps a few knowledgeable ones with the same mental outlook that act like they have a license to steal from these stupid idiots who see their engines as a complete mystery... but that is another lengthy story I won't become involved with right now.

Bottom Line: Sometimes I wonder, were we better off "Back Then", and if sophistication graduated to a point where it was possible to go back to those unsophisticated days... would I go?

Now.... Back to this fellows 1975 85hp problem...........................
 
I believe the original poster has not been on here since the 8th.-----So I believe he has the motor running like new now.
 
Huh? Nobody's reading all this good info, and its free? ......before the time of "techs".......back in the years of "mechanics". Excellent Joe, excellent! .......Even before the time of metric tools?
 
Compression test was correct. always getting a constantly 95 to 100 between all four cylinders. we check the spark you could jump more than 15mm we checked the fuel. we disassembled the carburetor we checked the fuel lines we check timing everything seemed correct. But still not starting we tried start you bastard multiple times new batteries the works.... nothing!!! :( until I adjusted this bolt which I think is 4 timing for idle!? I just needed to turn it one or two threats and it started straight away runs perfect starts every time again. thanks guys for all your help and hope this can help someone else maybe if someone knows what this one bolt is and share some light. Everyone has been a great help. thanks again form me and my friends
 
That bolt/set screw is simply the mechanical idle stop..... prevents the idle from dropping below a specified rpm from whatever you set it at.
 
Funny it would need to be adjusted. Apparently something is worn out and it wasn't getting enough throttle to start.
 
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