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I went to buy a 1978 Cobalt

jjohnson68

New member
"WELL, THEY SAID THEY REPLACED

"WELL, THEY SAID THEY REPLACED THE BALL VALVES BY THE T IN THE T-STAT HOUSING AND THAT HAS CURED THE MANIFOLD OVERHEATING PROBLEM.
WHAT'S YOUR KNOWLEDGE ON HARMONIC BALANCERS AND FLYWHEELS ON THESE BOATS?
THEY ARE SAYING THAT THE MECHANIC NOTICED THE HARMONIC BALANCER IS RUBBING ON THE COVER? HE SAID IT LOOKS LIKE IT HAS BEEN DOING IT AWHILE AND CAN NOT TELL HOW SEVERE IT IS. HE ALSO ADDED THE OL', "IT COULD BE ALRIGHT FOR A MONTH OR FIVE YEARS" COMMENT... I KNOW I AM BUYING A "30 YEAR OLD" BOAT AND CAN'T EXPECT EVERYTHING TO BE PERFECT. JUST WANT TO KNOW WHAT I'M GETTING INTO ON THE THINGS THAT ARE OBVIOUS. THANKS AGAIN IN ADVANCE!!!"
 
""JUST WANT TO KNOW WHAT I

""JUST WANT TO KNOW WHAT I'M GETTING INTO ON THE THINGS THAT ARE OBVIOUS."

A huge money pit! Please turn off your CAPS LOCK; it's considered yelling.

Old parts will break. If it ain't broke, don't fix it.
PN: 75420 BALANCER, HARMONIC - CRANKSHAFT $244.85"
 
when the balancer rubs into th

when the balancer rubs into the timing cover you'll then have a nice oil leak.
 
And we haven't even mentio

And we haven't even mentioned the integrity of a 31 year old hull...Floorboards??? Stringers????Transom????
 
"Alright,
Got the boat home l


"Alright,
Got the boat home last weekend and finally took it out last night. This boat ran like a striped ape and was a blast! About 50 to 55 MPH top end!The speedo pegged out at 50...
The trim works perfectly in the lower end but about half way up it stops like you took your finger off of the switch. If you jump the solenoid, it goes on up to the top like it should.
The next thing is we were out for about an hour or so playing around and all went perfect. When we came in to take the boat out of the water it started dying at an idle when put in gear. I had the bilge blower on. I re-started it over and over and each time it died when I put it in gear, forward or reverse. With all the dying, it would idle fine and throttle up in nuetral but it always died when put in gear. Any ideas on what could be the problem with either issue? FYI - the harmonic balancer was toast and I had it swapped with a new one for $100 parts and labor... Thanks again for all of everyones help!"
 
"The integrity of the hull is

"The integrity of the hull is excellent...
Floorboards are rock solid!
Stringers are rock solid!
Transom is rock solid and in perfect condition!
Here are pictures of it before I bought it, they haven't removed it from their website or marked it sold yet: http://www.ozarkvillageresort.com/index.php?option=com_wrapper&Itemid=42
I had it detailed by my automotive detailers that work for me and it cleaned up even nicer almost as new!!!
I just have some teak refinishing to do and the trailer needs some fresh paint. The teak is all great just the finish is wearing off and needs redone..."
 
"It sounds like a resistance o

"It sounds like a resistance on the shift cable most likely the short cable that goes to the outdrive. It is common when a motor get hot or with age. WHat is happening is,

At the shift bracket where the control cable and the short cable mount, there is a V notch piece with a micro switch that rides in the V. WHen you shift OUT of gear ( from reverse or forward TO neutral) the resistance on the short cable makes the V piece move and activate the switch, This momentarliy cuts out the ingition so the gears in the lower unit dissengage.

Now knowing this is how it is SUPPOSE to work, if it does this when shifting INTO gear it is due to several issues.

the most common is the short shift cable is old or has been exposed to excessive heat ( the cable lies on one of the exhaust horns behind the egine, left side)

Other issues would be the linkage in the gimbal housing is not moving freely. This requires the removal of the outdrive to see/test.

The other most common issue is missadjusted cables that allow the the activation of the V notch to switch when shifting into gear because you are over driving the short cable.

OK with that bieng said if it is a adjustment which you can do your self here is my basic adjustment proceedure.

This should get you in the ball park but if it does not then more investigation will be needed.

With the boat on the trailer,

1. raise the outdrive a couple of inches!

2. remove the short cable that goes to the outdrive from the bracket

3. push the plastic end IN and have someone turn the prop C'clockwise till it locks solid.

Keep the plastic end pushed in with light pressure.
4. measure from the center of the brass trunion to the hole where the screw went thru. 6 inches exactly no more than 6.
5. remove the control cable from the bracket.
6. install the short cable back on the bracket.

7. put controll lever into full forward full throttle position.
8 now adjust the trunion on the control cable so it fits in the bracket BUT do not install yet.

9 Now adjust that trunion on the controll cable 4 turns away from the plastic end.
10 install back onto bracket.
11. now shift back to neutral and make sure the pop spins freely.
12. shift to forward ( aprox 10:00 OCLOCK AND NO FUTHER!!) you should get full forward engagement when the prop is turned by hand c'clockwise.
13. pull the control back to neutral.
14. put the control into reverse (APROX. 2:00 OCLOCK NO FURTHER!!) YOU SHOULD HAVE FULL REVERSE WHILE someone SPINS THE PROP in the CLOCKWISE direction.

If not let us know.

This is a static adjustment. After this put it in the water and check it out.



This should be enough to work. If it still stalls then you will need more diagnostics and possibly a new short cable.


The trim switch is only to raise the outdrive a count of (one onethousand) (two onthousand) (three onthousand) That means approx 3.5 inches of trim ram extension. then it stops raising the outdrive. This is supposed to be the usable range while under power. There is a SQUARE button that will raise the outdrive the remainder of the way (trailer position)

OK did you get all of this?????

Wow what a pot of coffee will do for you first thing in the morning!!!!!!!!!!!1"
 
"Thanks Kghost,
I just went o


"Thanks Kghost,
I just went out and checked again for the square "trailer" switch. I've looked before and found nothing. But to my suprise, I found out how it works... There are two round buttons on the inboard side of the T handle of the throttle. There is another round button on the outboard side of the T handle I never found or felt before. After fiddling around with it, it requires both the top inboard and the single outboard buttons to be pushed simultaniuosly and "BAM" the trim works perfectly!!! Thank You!!! I might have went a long time before stumbling upon that myself or before someone else might have figured it out. Excellent website for info......
I am going to try to adjust the cable ends like you described but first I am going to take it out again and make sure it has the same problem dying twice. Maybe a glutten but just to curious to wait. If it does give the same exact problem as before, would it just be, the cable needs to be replaced because it is getting hot and causing the problem. Before it started giving me a problem last night, it shifted forward and reverse many times (very smoothly I must add) without any issues at all. If, when it gets hot only, my commen sense would tend to think it was just a heat issue on the cable. Would it help to shield the cable somehow? That is what I'll try to do before I take it out again first. At least tie back or something if it is resting on exhaust...
Yeah, you were sounding off like a machine, coffee does wind up people... LOL"
 
Once the cable is over heated

Once the cable is over heated that is typically it for the cable. There really is no way to shield the cable because the way it is routed.

You have the old style trim trailer switch arrangement

You need to get a owners manual for thet year boat.

Try the cobal website to see if they have them online.
 
"On the trim issue, the trim b

"On the trim issue, the trim button allows you to raise the drive only so far and it stops. This is to keep you from twisting the drive off the boat,literally!.Once max trim is reached by the "trim limit switch" the TRAILER button raises it the rest of the way for beaching or trailering or using IDLE SPEED only."
 
"Update:
I replaced the Roche


"Update:
I replaced the Rochester Quadrajet with an Edelbrock. For a few days it seemed to have fixed the dying problem. Now I have isolated the dying to only when the engine is at full operating temps and usually after at least an hour of running it. Within that first hour and while at normal operating temps, it does not die. But as soon as it gets to that 1st hour mark, it starts dying at an idle when putting it in gear and then it has started dying in nuetral also. It has also started having a problem even re-starting and running at all. Once cooled back down 45 min's or so, it will start and operate as it should. With the carb swap, I added a clear inline fuel filter and it appears to empty almost completely at times and as you run at 4k to 5k rpms for a awhile it slowly fills the filter to completely full...??? I am starting to think there is a fuel pump issue but don't know for sure. Also with the carb change: the boat has lost 10-15 mph and the rpm is wanting to rev to 6k rpms at w.o.t. and only get it up to 40mph max. The boat ran at 50+mph when first tested and it burried the 50mph speedo and seemed to have higher speed than it would clock. The throttle linkage did not match the new carb bracket and the O.E. throttle hold down bracket that mounted to the back of the carb had to be widened to fit the bolt pattern on the back of the new carb. The barrel that connects to the hold down bracket is adjustable by ext. threads on the throttle cable and int. threads on the barrel and I had to spin the barrel all the way to the end of the throttle cable threads closest to the carb which is approx. 2" from the barrels original location on the throttle cable. Could that have anything to do with the high r's and the loss of mph? Do you know of any other causes that might be affecting the loss of mph and high r's??? The throttle cable is also starting to bind up. When shifting to forward it releases from nuetral and has about 2"-3" of free play then the throttle is reached and you can feel it. Once you start to throttle up and then back down, the T-Handle seems to bind up and jam. You have to pull back pretty hard to get it to go back in nuetral. Same thing with reverse... To add to that, after several days of that happening, the last time I took it out of the lake, it would not disengage from forward gear unless I jammed it back into reverse then I had to jam it back into forward. It kept getting stuck in gear and would not go in nuetral until after 4 or 5 tries.
Overall, there have been a couple of different issues arrise since I changed the carb and my gut feeling and commen sense is saying it is related to that. Now with that said, I know components like the throttle/shift cables can fail at any given time, especially on older boats and vehicles."
 
You need to dump the edlebrock

You need to dump the edlebrock and go back to the original!! Or rework the brakets to work propperly.

Just so you know............there is absolutley nothing WRONG with the original set up.

They used that set up for over 20 years!!!

Just should have rebiult it!

As far as all of your other issues I personally do not have the abbility to try to teach you how to troubleshoot all of your problems over the internet.

At this point I would suggest to bring it to a very reputable marine mechanic and let them have at it.

Too many issues or potential issues to resolve here. Sometimes this is what happens when a boat sits for many years without use.

Good luck
 
"Copy that loud and clear!
I


"Copy that loud and clear!
I had just dropped the boat at a good mech this morning after posting the message. I am always trying to learn new things and do repairs on my own as much as possible. So, This website seemed to be a great place to help with diag's and/or if nothing else some pointers or suggestions on what might be wrong. A good mechanic could always benifit from other good opinions and/or experiences in some cases to assist in diag's, especially when there are weird off the wall issues.
As mentioned before, it has had several issues that seem to be coinsidental in terms of all happening right after I swapped carbs. For all to have failed and/or the issues that have arrised at the same time on a boat that has sat for a long period could happen too..."
 
""Experience is something

""Experience is something you get, right after you need it"

Most of us have been there. Testing it out on the water after you made the negociations is something you and I will never do again. Sorry for your pain but it sounds like you will learn more about your boat than you ever wanted to!

I know, I'm not being a bit of help...but you found the right place to get back on to the water."
 
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