More failure for me!

[Uraijit]

Got my engine (5.7L Chevy) running on muffs, timed her up, and did a cam break-in (just in case, because a couple of lifters got mixed up during the rebuild) and splashed the boat today. It took about 10 min of idle speed to get out of the no-wake zone, and I hated every second of it, because low-speed's no good for new engine break-in.

My wife was piloting, because she has more boating experience than I.

Literally 10 feet short of the no wake buoys, we went to throttle up a little, and as soon as she touched the throttle, it died. Wouldn't re-start no matter how I coaxed it. It got real close a couple of times, but eventually drained the battery. Ended up getting towed back in. Got a couple of "been there" comments from folks passing by while we got towed (and a lot of looks that said the same). Once we were back on dry land we headed home in shame.

Took her home, and after about 5 min. of cranking, got it to fire up and idle just fine. Still dies as soon as you give it much throttle. I can ease into it, and get it up around 2500 RPM, but any sudden throttle change, and it dies. Gonna try a new coil and wires (the coil wire is pretty shot). Since the problem didn't come around until the engine was pretty hot, I'm thinking the coil might be the culprit.

My reasoning is that a weak coil could have enough juice to give a good idle, but as soon as it sees more fuel, it creates too much resistance for it to spark, and stalls out? I've seen it before on some vehicles, but this was all old technology by the time I started wrenching, so it's not something I've dealt with a lot.

Same story with carbs--before my time. It's got a Q-Jet carb, and a buddy who's pretty familiar with 'em said the carb probably doesn't need a rebuild, as long as the accelerator pump is still good? It works just fine; pump the throttle, and the primaries get a good strong spray of fuel.

I hooked the fuel line straight up to a gas can with brand-new gas in it, to see if it would make a difference, and it still ran the same, so I know it's not bad gas. I even went to the effort of draining the water separator so that it would be all fresh gas going into the carb.

Anybody else got any suggestions for what it might be? The engine was getting warm from idling for so long, but it wasn't "hot" by any means. I wish my gauges actually showed real temp numbers, but it's just got a green zone. It was about 85% up in the green zone...

 

[JustJason]

Re: More failure for me!

well.... before you go tearing into everything.... whats your idle timing, and is it advancing with the throttle?

 

[Uraijit]

Re: More failure for me!

Idle timing is 8deg BTDC. It is advancing properly. I don't think it's an advance issue though, because the engine doesn't rev up before it dies...

 

[JustJason]

Re: More failure for me!

if you can ease into some rpm's but a slam of the hammer kills it i'd be looking at the accelerator pump.
disconnect the throttle linkage, open up the choke plate with your fingers (do this with the engine off!!!) give the throttle 1 firm quick pump.
Do you see 2 steady streams of fuel discharge just next to the nozzles in the carb venturi? you should get 2 streams (1 per barrell) every time you pump the throttle.

 

[Lou C]

Re: More failure for me!

Could be ignition, but sounds more fuel related to me. One thing to check is your basic timing and advance at higher RPM. When I had this problem with my 88 OMC I went thru the whole ignition system, everything checked out OK, points setting, timing and advance. Then to the fuel system, carb seemed to be working as far as accel pump. Finally took it to a good mechanic, there were 3 things contributing: corroded anti siphon valve, restricting fuel flow, carb needed a good cleaning, and the transom shift cable was sticky causing the ESA to engage when the engine was in gear. I'd check the anti siphon (mounted on the gas tank) pick up in the gas tank and the fuel pump.

 

[bruceb58]

Re: More failure for me!

Literally 10 feet short of the no wake buoys, we went to throttle up a little, and as soon as she touched the throttle, it died.

Sounds like a carb problem to me. It was either running really rich while you were idling, loaded up and possibly fouled your plugs. Of course the other possibility was that it was running extremely lean. It ran good for awhile since the choke was on and once the choke came off, it was too lean. How's that for covering by bases?

I am hoping that you did all the general things like measure the dwell with a dwell meter, timing, new cap, new spark plug wires and new plugs...right?

I really doubt its your coil. I wonder how many people have spare coils in their tool box becuase they bought a new one thinking their coil was bad. Come to think of it...I think I do...but it was many years ago when I didn't know any better.

 

[Limited-Time]

Re: More failure for me!

Sure sounds like an accelerator pump/carb issue to me.

 

[Uraijit]

Re: More failure for me!

Alright guys, sounds like you're all telling me everything I don't want to hear... I guess that makes you true friends, right

I'm going to go ahead and replace the coil wire for sure, because the boot is starting to fall apart, and the wire is starting to move inside the insulation. But I guess I'll pull off that carb, and see what I can see. Maybe it just needs some cleaning.

If the accelerator pump still sprays fine when I pull the throttle, is there still a possibility it's bad?

 

[chiefalen]

Re: More failure for me!

I know you have a problem, BUT HOW MANY THREADS YOU GONNA START WITH THE SAME ISSUES?

 

[Fishermark]

Re: More failure for me!

If the coil wire is "pretty shot" then by all means replace it and see if that solves the problem.

But it sounds like a carb issue to me. I would be willing to bet you sucked up some bad fuel and you still have some nasty stuff at the bottom of the fuel bowl - simply hooking up to another tank will not solve the problem if that is the case. If the coil wire doesn't solve your problem, then it is time to take the top off of the carb and have a look inside the bowl.

 

[Uraijit]

Re: More failure for me!

I know you have a problem, BUT HOW MANY THREADS YOU GONNA START WITH THE SAME ISSUES?

I started 1 new thread with this issue. What are you talking about? I put an update on a thread I started months ago, as to my progress. In that thread, I mentioned the problem, and decided to start a new thread, rather than hijack my old thread... I hear that's what you're supposed to do. Am I wrong?

Anyway, FINALLY, some success for me!


The problem "felt" for all the world like a spark issue to me. I decided to go back and take another look, and see what I could figure out.

On the way over to look at it, I had an epiphany! "Did I remember to tighten the distributor back down, after setting the timing?

Sure enough, got there, grabbed the distributor, and it spun in my hand. Pointed it back at the #1 cylinder, fired it up, threw the timing gun on her. Got her timed, and then thought "Oh S***, did I turn the water on after I put the muffs on?" Killed the motor real quick. It had been running for about 30 seconds.

Turned the water on, and rechecked the timing. Timing still good, I locked the distro down tight, and let her run for a good 20 min. Water still circulated through the engine, so the impeller lived.

Went back out and splashed her again. She worked like a charm! Temps were actually lower than yesterday, so the impeller is still good.

Went out for a couple of hours, and even got pulled behind a tube for a while, as a reward for all my work I've put into it over the past 4 months!

Going back in, I heard a little clicking while I was docking whenever I'd turn the drive. I guess I gotta replace those U-Joints after all, but I'm okay with that. Gonna check the gimbal bellows for water intrusion, and take her back out tomorrow afternoon for Utah's big holiday (July 24 is "Pioneer Day". Big state holiday).

Thanks again to everybody!

 

[MikDee]

Re: More failure for me!

Well, How about that! Been There, Done Stupid things like that myself occasionally. Glad you got it fixed, and let us know, Good Luck, Mike

 

[JustJason]

Re: More failure for me!

only took 13 posts to do what i said in post 2

 

[TommyA]

Re: More failure for me!

I really appreciate it when thread originators give the final results to the problem presented. Unfortunately there are countless threads in the archives that were never finished therefore making them useless for future troubleshooting. Thanks Uraijit for the update!

 

[Uraijit]

Re: More failure for me!

only took 13 posts to do what i said in post 2

Yeah, way to be on top of that. The timing WAS set, but, retard that I am, I forgot to snug it back down.

I really appreciate it when thread originators give the final results to the problem presented. Unfortunately there are countless threads in the archives that were never finished therefore making them useless for future troubleshooting. Thanks Uraijit for the update!

I feel the same way, I hate cliff-hanger threads that never get resolved.

 

[Uraijit]

Re: More failure for me!

Well, there's not a happy ending to this story just yet.

This brand new engine build has maybe 3 hours on it. Today, after our success yesterday, we decided to take it out on the lake for a little more fun. Spent the early part of the afternoon replacing the U-Joints. Bent the yoke on the input shaft pressing them out, but got it straightened back out. Took about 3 hours to do a 1 hour job, but we got her done.

Got her launched, and because it was a big state holiday, lake patrol was out. We got stuck behind them going SUPER slow in the no-wake zone, and they kept slowing down to yell at people coming back in the channel. It already takes about 10 min. to get through it, because it's way long. But I wasn't about to pass them and give them a reason to harass me.

I'm really not doing this new engine any favors by idling it like this for so long...

Once we got out on the water, we put out a tube and towed it for about 5-10 min.

Started losing power very quickly, (wouldn't move above 15mph). Looked at the gauges and saw 0 psi oil pressure. Shut her down quick, and opened the oil cap. Smoke came pouring out. Didn't have extra oil (that's been remedied now--I won't make that mistake twice), so after about 300 yards of swimming /paddling back in, we finally got someone to come over and give us a tow (lake patrol was nowhere to be found when they could have actually done some good, of course).

Anyway, got her back home, put some oil in her, and fired her up. Oil pressure went right back up to about 45psi at idle, and about 65psi at 2000rpm and above. Noticed a little bit of valve train noise for the first few min., but it seemed to go away.

I guess I'll go test her out again tomorrow afternoon, and see if I've trashed this engine or not. I should probably go get a compression gauge see if the rings survived or not... It's only going to cost me $100 or so to rebuild it again, but still, it's going to be SUPER frustrating if I have to do it again.

I know it's my own damn fault for not staying on top of the oil level. I know new engines tend to consume a fair amount of oil during break-in, but I didn't think it would consume 4+quarts in 3 hours of use...

This has been a bad week for the Ijit crew (seems like an especially fitting name right now). 2 tows in 3 trips is not a very good record to start out with.

And my wife said she was hearing a bit of noise from the outdrive when the engine is revved. I couldn't hear it, but she swears it's there... I think the U-Joints solved my turning noise though, so I guess that's a good thing.

On top of that, my wife's Honda Civic died on her today as well. I towed it home, but I didn't get time to look at it (it was well past dark when we got it home).

Aside from my business being on the rocks due to a supplier threatening to turn tail, my luck just keeps going further and further South...

Wish me luck on this engine living through the punishment I just put it through. I could REALLY use some good luck these days.

 

[Fishermark]

Re: More failure for me!

I know new engines tend to consume a fair amount of oil during break-in, but I didn't think it would consume 4+quarts in 3 hours of use...

Nor do I. If it did in fact burn / use that much oil in that time you have bigger problems ahead.