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Paragon HF-7 being too tight

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Mark Christensen
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Paragon HF-7 being too tight

Post by Mark Christensen » Tue Aug 09, 2011 8:41 am

I have 2 - 283's in my sea skiff with Paragon HF7 transmissions. My port engine I can leave at idle and shift back and forth with no issue. My starboard engine, if I am at idle and try and shift, it almost always kills the engine. So I have to race it to about 1500RPMS. The manual says that it's ok to do this in an emergency, but not on a regular basis. Does anyone know what could cause this transmission to be "stickier" than the other?

minor detail that maybe important...when i do shift on my starboard engine, it doesn't kill the engine right away, it's as if it has to actually shift into gear, then the resistance is too much for the engine and it dies.
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Post by mfine » Tue Aug 09, 2011 9:00 am

That could also be a vacuum leak causing the engine to die and not an issue with the Paragon having too much resistance.

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Post by Mark Christensen » Tue Aug 09, 2011 9:19 am

aha, can you elaborate on vacuum leak? How do I troubleshoot? What exactly is a vacuum leak? Feel free to send me to google to figure that out if it's obvious.


could this be true also if my port engine is definitely stronger and I have to compensate with more throttle to my port?
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Post by mfine » Tue Aug 09, 2011 9:36 am

Vacuum leak basically means the engine is sucking air in from somewhere other than through the carb venturis.

It will throw the mixture off, more so at idle, and less at full throttle. It could be leaning out enough to stall under load at idle, but not enough to stall at 1500 rpm. An engine running too lean could be producing less power, again I would expect it to be more noticable at lower throttle settings and less so at WOT.

There are a number of ways to track down a vacuum leak, google should help. In a boat you don't have all the vacuum lines you have in a car, so it is most likely right on the intake or carb. One trick I know is to spray suspected areas with carb cleaner while at idle. If you hit the leak it sucks it in, and the idle speed will go up (less lean).

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Post by Mark Christensen » Tue Aug 09, 2011 9:47 am

hmm interesting. Yeah the engine runs pretty well at WOT. It's just at idle that it's touchy when shifting. I'll try the carb trick tonight and see if I can't track it down.

Next question is that my port engine runs GREAT once I get it running. but to get it running I have to spray carb start into the carb because I cannot prime the engine using the throttle. Once it's warmed up and fuel is pulling it's fine. Is there a primer "pump" or something similar that is different than the normal fuel pump???
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Post by mfine » Tue Aug 09, 2011 2:48 pm

That problem has a lot to do with modern fuel, especially with ethanol. The fuel today is much more volatile and it can evaporate out of the carb when the boat sits, especially if it is more than a few days. You need to turn over for a bit in order to allow the fuel pump to refil the carb before there is anything there to prime with.

The only real solution I know if is an electric fuel pump which pumps quicker than a mechanical one when the starter is engaged, or manually filling the bowl which is a pain.

To deal with the problem as is, crank the engine over with the throttle closed without any throttle pumping for a bit. Experience will eventually tell you how long it takes, but I try not to turn it over for too long without a rest because starters do not have cooling provisions. Maybe a couple of 10 second bursts.

When you think it has fuel, or if it seems like it is trying to fire, stop, pump the throttle all the way to full 3-4 times. This actuates the accelerator pump to squirt some extra gas into the intake (poor man's priming). Bring the throttle back to a cracked possition, usually not fully closed but more like a fast idle possition. Crank and it should fire up or try to. If it does not fire after turning over a few times, crank more with the throttle closed to let the fuel pump work a bit more. If it sounds like it is firing but does not start, pump the accelerator pump a few more times and try again.

Note, don't pump the throttle too much or too soon or you will pump gas out of the bowl you are trying to fill, but not enough for the engine to fire, so it will take longer to start not shorter.

This process should work for most installs unless something else is wrong. For example, it worked great on our 76 Penn Yan with a Quadrajet carbed 350 until early July when it started to need more and more cranking, and a little starter fluid. That turned out to be a warning sign that the fuel pump was dying. It has been replaced with an electric pump and now it starts up much quicker even after sitting for a week.

Another potential (likely?) problem is the accelerator pumps can go due to the wonderful effects of ethanol. In that case you lose the priming squirts which can make it harder to start. You can easily verify this by pulling off the flame arrestor and holding open the butterflys. Look in while you pump the throttle to full and you should be able to see the fuel squirt in.

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Post by Mark Christensen » Tue Aug 09, 2011 2:59 pm

I can never get fuel to squirt in on the port engine. That's why I use the carb start. I am interested to try your explained method though.
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Post by jfrprops » Tue Aug 09, 2011 3:12 pm

Just an added thought: I have experienced engine issues when I too thought they were certainly Paragon issues.

If you have a COIL RESISTOR, especially the older version that is a ceramic exterior resistor near the coil, when those go ( burn out ) you can not get the engine to power up properly to get moving from idle.
There being too much starter "juice" going thru the points and etc...shorting them out...

This has more than once been the ACTUAL problem when folks thought/felt it was the gear box binding.

See if you have that resistor. There have been detailed post about that problem on this site,....check in archive?

The carb leak suggestion is a good one, and maybe more likely...

John in Va.
1980 Fairchild Scout 30
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Post by mfine » Tue Aug 09, 2011 3:15 pm

If there is no fuel in the carb from evaporation you will not see a squirt but the accelerator pump could still be working fine. After you get the engine to start and it runs for a minute or two, shut it off and check for the fuel squirt. Also, I am assuming that one you get the engine to start, it restarts fairly easily.

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Post by jfrprops » Tue Aug 09, 2011 3:16 pm

Also: mfine has very good and specific advice about his STARTING SEQUENCE. Lots of us have eliminated the choke on these engines and just pump to start...so that sequence he lists is right on.

I don't like the idea of an electric fuel pump (or 2) under the hatches in these big old cruisers...for obvious reasons.

John in Va.
1980 Fairchild Scout 30
19?? custom Argentine Runabout 16'
1954 Whirlwind deluxe dual ckpt 16'
1921 Old Town Charles River 17' (founding Captain, James River Batteau Festival)

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Post by mfine » Tue Aug 09, 2011 3:35 pm

Proper electric fuel pump install with an oil preasure cutoff switch has some safety advatages (and disadvantages) over the old mechanical pumps with diaphrams that fail. I think they are pretty standard on new installs so I would not dismiss the idea entirely. Just do it the right way with coast guard approved components and no cut corners.

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Post by davidvn » Tue Aug 09, 2011 9:34 pm

Mark
If it shifts into reverse ok but not forward it could be that the reverse band is set up too tight. This would lug the engine down at idle.
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Post by rgmxk22 » Tue Aug 23, 2011 7:25 pm

Mark,

I'm curious when you say the transmission is tight, when you do get it shifted, does everything seem OK with the trans? Or when it's in neutral, for you see the shaft slowly turning/creeping?

I ask because if the issue is with the trans itself and you see the shaft turning in neutral, you could have warpped clutch plates in that trans.

Ron Michael
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Post by Paul P » Thu Aug 25, 2011 4:58 pm

Just a comment on the vacuum comment. There are seveal versions of the 283 so my comments only apply to the ones with the PCV valves and "positive" ventilation, which means the PCV valve draws fumes via vacuum from the intake or carb from one valve cover, and clean air enters the other valve cover, providing a positive cross flow to evacuate the crankcase. Old style systems just have a tube near the carb to catch the stink, and these are not PCV systems.

A faulty (stuck open) PCV valve will functions as an open pipeline directly into the vacuum system when it is open, which is most intended to be when engine speed is high enough to create sufficient vacuum to pull the internal piston up into the open position. You can tell if your PCV is working okay by just running the motor at idle and pulling the tube off your carb, if the speeds up your PCV was closed as it should be and it is working okay. If nothing happens it is likely the PCV is stuck open and you have compsated for it by tuning to the best you can. It will create poor running at low speeds, but at fast running it would be far less noticed because the PCV valve would be wide open at the time anyway. There are many different types of crankcase ventilation systems, but the POSITIVE crankcase ventilation systems will function like I mentioned. If your system is a passive system just intended to draw in any fumes that migrate out the end of the tube, then my comments do not apply.

regards,

Paul
1956 17' CC Sportsman, 300-hp
1957 17' CC Sportsman, 95-hp
1966 20' CC fiberglass Sea Skiff, 210-hp+
1973 23' CC Lancer inboard project, 427/375-hp.
1966 38' CC Commander Express, 427/300-hp(2)

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Post by Mark Christensen » Sun Mar 25, 2012 11:03 pm

Ron and Paul, these are interesting points.

First off I've now noticed Both engines require revving to about 1500 rpms to shift without stalling. That being said when they are in neutral there is a little spin from the props but not much.
At neutral the engines idle perfect. Once they are in gear they run great all the way to WOT. It's just the initial shift into forward AND reverse that I have to rev to keep them running. Still haven't fixed the problem. Would love any help.

Also when transmissions are in gear there is no slippage or anything that would signal a red flag.
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Post by Peter M Jardine » Mon Mar 26, 2012 7:41 pm

I had a similiar problem with idle on one of my 283's. I replaced the fuel pump, plugs, wires, swapped out a transmission....it could be points not set properly, weak coil....timing off...

It was dirt and crap and an ancient carburetor. I rebuilt the carburetor and it runs like a champ. If the engine dies when you put it gear, there are numerous carburetor problems that could be there... no vacuum, shafts on the carb sucking air, the choke circuit not functioning properly, and dirt in the bowls and jets, and finally a float not set properly. PLUS all the other things mentioned by other posters.

If you have 283F engines, they typically use a 3660S Carter carburetor whic is easily rebuilt by a good carb guy. The most complete kit for that carb is available from these guys, and is a very reasonable price. The kit includes main jets, dash pot plunger, gaskets check balls etc, all for that specific carb, $60.00

http://www.thecarburetorshop.com/Marine ... m#MkitCCft

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Post by Mark Christensen » Mon Mar 26, 2012 7:50 pm

Peter, I bet this is it, because I rotated the transmissions by hand today and there is hardly any resistance. Who knows when my carbs were last gone through, I'll do that this week and see how it goes.
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Post by Peter M Jardine » Mon Mar 26, 2012 8:58 pm

It is certainly my best guess. Have your carburetors dunked too, so they clean up the castings, then reassemble them. The other detail is to make sure you have heat wrap on your choke tubes coming from the exhaust manifold to the choke assembly.

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Post by Mark Christensen » Mon Mar 26, 2012 9:14 pm

dunked?

Do you have any pictures of your carbs?
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Post by Paul P » Tue Mar 27, 2012 9:31 am

Looking back at the thread again, I would agree it is a carb issue if the boat it properly timed to the mark on the flywheel and not some other spec. CC used the timing at flywheel at generally 500 RPM, and this differs from what you would see on an automotive application. On the 427 it is about 10 degrees BTDC but I don't know right off hand what it is on the SBC motor, but in any case go for the mark on the flywheel and not some other sort of timing. Valves too tight will also cause poor drivability. Too much air (lean mix) will cause engine to lose power down low, and I mentioned this when I noted the PCV system.

I'll use the 427 as an example because that is the one I am most familiar with, but it applies to all motors that use the PCV and route it to the carb...if you deactivate the PCV then engine speed goes up, and you can tune it back down but when you do it has no real charge for pickup down there and it will stall out more easily....it will also run just fine at higher rpm. You could have an air leak in the manifold somewhere, worn linkage at the carb, open port somewhere like the emergency fuel bypass, or stuck PCV or no PCV...which should be fully closed at transmission shifting times to give the carb a full charge.

good luck,

Paul
1956 17' CC Sportsman, 300-hp
1957 17' CC Sportsman, 95-hp
1966 20' CC fiberglass Sea Skiff, 210-hp+
1973 23' CC Lancer inboard project, 427/375-hp.
1966 38' CC Commander Express, 427/300-hp(2)

So many boats.........so little time.....but what a way to go!!

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Post by Mark Christensen » Tue Mar 27, 2012 9:39 am

Is it worth doing a rebuild on the carb to try and solve the problem? I wouldn't think it was timing if the engines run perfect otherwise?

And is rebuilding a carb something I could do on a saturday if I had the parts/kit? I would take apart the port, and use the starboard for reference. Then put the port back together and repeat with the starboard.
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Post by mfine » Tue Mar 27, 2012 10:08 am

What kind of carbs, and when were they last rebuilt?

If you ruled out a vacum leak or PCV issue, it is easy enough to check the timing assuming the installation allows you enough access to see the timing mark. Might as well check that before you pull the carbs.

If it has been a while since the last carb rebuild, it wouldn't hurt to rebuild one and see if it solves the issue. I guess you could just rebuild them both, but I would be careful about introducing too many new variables at once.

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Post by mfine » Tue Mar 27, 2012 10:25 am

Here is a fairly thorough video series on a quadrajet rebuild that will give you an idea of what is involved. Plan on it taking you longer if this is your first one. Other carbs will be mostly similar and certainly not worse, and I am sure you can find other videos. Also a lot of rebuild kits come with decent written instructions.

http://www.boatered.com/forum/topic.asp?TOPIC_ID=133180

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Post by Mark Christensen » Tue Mar 27, 2012 10:29 am

I have no idea when the carbs were last rebuilt unfortunately. I've only had the boat for a year. When he sold it to me, the last owner said "yeah the transmissions have always been 'tight.' " I wonder if he just didn't realize there could be an engine/carb/timing problem.

If I could get this fixed I'd be super happy.
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Post by Mark Christensen » Tue Mar 27, 2012 10:49 am

Do these look like Carter carbs? I know they are low res and I'll double check tonight, but I'm just curious:


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Post by mfine » Tue Mar 27, 2012 11:55 am

Hard to see on my phone, but my best gues is those are Rochester 4G's.

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Post by Mark Christensen » Tue Mar 27, 2012 12:48 pm

are Rochesters easier/harder to rebuild? It seems the rebuild kits are cheaper.

Also after these revelations, does any of it explain why I can't pump fuel into my carb on my port engine? I have to spray carb start in and then it pulls the fuel fine?
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Post by mfine » Tue Mar 27, 2012 2:16 pm

Basically you are taking it apart, cleaning out years of debris and buildup, and then reassembling while replacing a few key parts that wear with new one. The process is 90% the same on just about any carb, with minor differences on what parts need replacing and where things go. The biggest headache is usually finding the little check ball that rolled off the counter and/or spring that lept away and simply vanished.

Before you get started, you are going to want to visit the boat and get the tag number for your carbs keeping in mind that after all these years the two may be different. Get a kit for your carbs that covers the tag number, and that explicitly states that the components are made for gas with alcohol/ethanol. The accelerator pumps are vulnerable to ethanol so if you get a cheap one, you could be at this again in a year or two.

Chances are you want the first kit in the link below or a similar kit from your supplier of choice. They have a decent link on how to find the ID number as well.

http://quadrajetparts.com/rochester-4gc ... 4_123.html

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Post by Mark Christensen » Tue Mar 27, 2012 2:18 pm

Sounds like the plunger in these is what delivers fuel for starting. I bet mine is shot. I'll visit the boat tonight and see what the numbers are. Sounds like a fun saturday project.
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Post by mfine » Tue Mar 27, 2012 2:30 pm

Mark Christensen wrote:Also after these revelations, does any of it explain why I can't pump fuel into my carb on my port engine? I have to spray carb start in and then it pulls the fuel fine?
If by not pumping, you mean it wont start even after lots-o-crankin on the starter, I would suspect your fuel pump is on the way out. If you mean no squirt from the accelerator pump when you pump the throttle, even when you test right after shut down, that is a possible (likely?)casulty of ethanol. No squirt after the engine has sat cold for a few days could simply mean that there is no fuel in the carb to pump.

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