Evinrude 175 bogging acts like it's not taking fuel

[gwgautney]

Ok boat ran good all day Friday until I got ready to head in. Took off from rig and boat bucked and wouldn't take fuel. I had my friend pump bulb and it took off as and ran fine as long as he pumped the bulb. I bypassed filter to make sure it wasn't clogged filter and no change. Now when I got home and was going to run it it acted like it was locking up. It would turn over a couple times and stop. It did this a few times and then turned over and cranked. It will rev fine on the hose. Checked compression bottom left cylinder was 90 the other ones were 100 to 105. Trying to figure out if I have dropped a cylinder or a head gasket or fuel pump.

 

[1983 ercoa 21']

It would help to know what year the motor is.
yes it sounds like a fuel delivery problem which could include a fuel pump or a fitting sucking air.
the one cylinder is a little low but not far from the 10% difference.
a decarb treatment may help with the compression.

 

[gwgautney]

Year motor is in my signature along with model and make but it's a 98

 

[1983 ercoa 21']

I see it now lol

 

[gwgautney]

What concerns me there most is how it acted like it was trying to seize up

 

[1983 ercoa 21']

Pull the head on the low side and have a look at what's going on a bad fuel pump causing the motor to run lean isn't good on a two stroke as this is how it gets it's oil also.
if you know someone or a local shop that has a bore scope you can have a look that way without pulling head.

 

[gwgautney]

Ok going to pull it this week. What is the sealing compound I see between the block and the head in this motor. I want to go ahead and order my o rings and have that stuff on hand

 

[1983 ercoa 21']

I'd pull the head and see what's going on before ordering any parts yet .
you might find out you need alot more than what you have ordered but hopefully not.

 

[gwgautney]

Ok will do

 

[gwgautney]

Ok will do

 

[gwgautney]

a little update, I rechecked compression today and bottom two cylinders were about 97 top 4 cylinders were all right around 104 so now I'm thinking it's not anything internal although I have heard something about decarbing an outboard what and how do I do that. I'm going to run it on external tank tomorrow evening when I get in and see what I come up with

 

[1983 ercoa 21']

If you have a local omc dealer they will have some on the shelf.
some Use sea foam .

 

[1983 ercoa 21']

When you had the plug out did you roll piston to top dead center and use a light to look at the top of the piston to see if there is any marks that a broken ring would make which would explain the not wanting to turn over?

 

[gwgautney]

No I did not do that

 

[1983 ercoa 21']

It wouldn't hurt and don't cost a thing. Just a peace of mind.

your latest compression test is alot better.

before replacing that high dollar bro fuel pump check all your lines and make sure you are not suckin air.

 

[gwgautney]

Will do it was odd that it did it all of the sudden ran fine all day then cranked up and idled away from rig and when I gassed on it bam it did bad

 

[gwgautney]

ok took it out and ran it today and took an external tank with me. I am able to ease it up and run at about 4000 rpms fine but if you try and go above that its like its not getting enough fuel and starts bogging again. I switched back to the onboard tank and it does pretty much the same thing. I am at my wits end with this. Going back a few months over the winter I restored the hull. I ran the motor on the hose several times during the restore. From day one after putting it back in the water I have had an issue with this. Ive cleaned and rebuilt carbs. I did away with anti-siphon valve and that appeared to fix it for a couple months but the problem has reared it's ugly head again. How would I check the fuel pump or does it sound like pump to yall. I'm going to eliminate the hose from the tank to the bulb because I switched to external and had problems also. The bulb is only a couple months old and it's a good bulb not a cheap Walmart one. so where do I go now? what really gets me is before I took the boat down and did all the work over the winter I did not have this problem but first time out it was bogging at higher rpm's and has gotten considerably worse over time or at least it seems as if it has. It may be all in my head. Just about ready to trade it for a jon boat with a trolling motor on it.​

 

[1983 ercoa 21']

You can put a t in line after fuel pump and get a fuel pressure gauge and do a test or when you have it out pump the bulb when it starts bogging if it clears up you have a delivery problem which could be the fuel pump or a leaky connection.

 

[gwgautney]

if you pump the bulb it does clear up. Where all would the leaky connections be because it's not before the motor.

 

[emdsapmgr]

These later looper 60-degree V6 engines do run lower compression on the lower two cyls. That's normal. This is a factory design, so there is no problem with the engine. It's for the long-term durability of the powerhead. Agree with post #18. If you can't get the engine to run correctly at WOT without constantly priming the fuel hose bulb-likely your engine is running lean-which can include a weak fuel pump.