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Twin Chrysler inboards will not go over 3300RPM

"I was able to get a hold of a

"I was able to get a hold of a timing light that had a meter on it. After setting the timing at book rated 5*BTDC we reved the port engine, in neutral up to 2000 and 3000 RPM. The timing advanced 12* and 14* respectively for a total of 17* and 19*. Did the same to the port engine and the timing advanced 9* and 12* respectively for a total of 14* and 17*. We took both distributors out and are having them rebuilt as we speak. Should have them back next weekend. Any ideas on what to do if we cannot get anymore advance?

We still have not been able to get the boat out after resetting the floats to give us a little richer mixture. We boat in Lake Erie at Catawba and the winds have not been in our favor the last couple of weekends. I did the Seafoam deal and picked up another 100 to 200 RPMs but have not been able to test it. I also bought octane boost but have not put that in yet either. I think we will switch to the high octane gas which does not have ethanol. We also have two carbs from a friend who had his 440's rebuilt and had his replaced. WE have the carbs but have not tried them yet. One thing at a time. So we have work to do but I'm still wondering about the distributors and if we cannot get full advance. I am thinking of setting the distributors at 10*-15* rather than the rated 5* and making sure we do not get any preingnition ping and see what happens. Any thoughts????"
 
"Some how or another you need

"Some how or another you need to get the full 26 to 28 (or so) degrees of advance. The motors may start hard (fight the starter) with so much initial advance, but I'd try it anyhow.

How confident are you in the timing light's accuracy? I'd check it against a motor that sure to be running okay before proceeding further.

Jeff"
 
"Jeff, Check the timing with

"Jeff, Check the timing with 2 lights. Same results. Just got both distributors back from rebuild guy and he says they were fine. Replaced one spring but didn't even charge us. That said, I don't understand why we cant get full advance. Any Ideas?

Tomorrow, we will set the timing so full advance is around 30*. That will probably mean the idle timing will be about 15* rather than 5* as the book calls. We'll see. Still stumped as to why it won't advance on it's own.

Don"
 
"With the lower compression ra

"With the lower compression ratios of marine engines, you might be okay hot starting it with that much advance.

Got my fingers crossed!

Jeff"
 
"After talking in person to th

"After talking in person to the rebuilder of the distributors he said that he replaced all springs with weaker springs. This past weekend, I set the timing at 5* at 500RPM. Ran the engines up to 3000RPM and we were advancing to 38* on both engines. What a difference those spings made. From 14-19* with the stiff springs to 38* with the weaker spings.

We took the boat out and ran to 3800-3900RPM and 32MPH. Wow!!! That is the first this boat ran that in years. After running hard for about 10 minutes we started to lose RPM on the port engine so we brought it back to about 3000RPM and were running at 22MPH. She backfired a few times as we backed her down. Still wondering about the fuel pumps and if the engine started starving for gas.

Anyhow, we are extremely happy with the results. Never would have got to this without the suggestion to go to a metered timing light and check full advance. I think we will still put in new fuel pumps and get the extra set of props turned to 19x21 instead of the 19x22 that are on the boat. I also think that the seafoam made a difference by about 150RPM. Lastly, I'm wondering if we are now getting too much total advance. We need to run the boat for an hour to see how she runs. The engines sounded great though, aside from the backfiring.

Thanks everyone for all your help!!! Remember those timing springs. The rebuilder said they have been doing that because of the cheaper unleaded gasoline now being used."
 
"That's a bit more advance

"That's a bit more advance than recommended--a bunch more! It's 26 degrees max on a 318/ 360. Not sure what a 440 is, but that sounds way too high and might be the cause of that backfirng. Not good!

Jeff"
 
"It isn't good to start wi

"It isn't good to start with 38* timing in a boat as big as yours. Yes, 38* in a 440 will make the most power, but your boat and motor combo has too much load on the motor to be able to take 38* for extended periods. I run 35* in my boat but it's only 19' and turning a 14x14 prop, my motor doesn't have near as much load placed on it as yours does.
I'm also not sure what the factory setting is for a 440, probably 28*-30*. A 440 needs a bit more than a 318/360 due to chamber design and bore size. Factory settings are conservative to allow the motor to be used in any boat application without fear of damage from more timing than the boat and motor combo could take.
Pull the plugs and check them, your RJ14YC plugs are a bit hot, the electodes could have been burnt off. I'd start off at 32*, install RJ12YC plugs (a bit colder and will allow more timing), run it and then read the plugs. Plug readings will can tell you several things. too little or too much timing, correct plug heat range, correct air/fuel mixture and if the motor has experienced detonation. Plug reading is one of the best tools on how to tune a motor for best performance. Here's a couple of links on how to read a plug.

http://www.dragstuff.com/techarticles/reading-spark-plugs.html

http://www.4secondsflat.com/Spark_plug_reading.html

Even with all the high tech equipment and engine dynos the the NASCAR teams have available at the shop, the engine crew still pull the plugs at the track and read them to see if the motor needs further tuning."
 
"As far as dist mech advance,

"As far as dist mech advance, different weight springs are used to adjust how fast the timing comes in. The springs are attached to weights that are slotted, the slot length determines how much advance will come in, the longer the slot the more timing. The weights are marked with a number and letter, example a 9R weight will allow 18*, a 11.5R will allow 23*, the dist turns at half crank speed so double what the number is stamped on the weights for how much timing they will allow.
According to the factory dist specs, marine dists have light springs for the timing to come in at low RPM, most of it all in by 1500rpm. Autos on the other hand, won't see total timing till 3000-4000rpm so they have a heavier spring to delay the mechanical advance from coming in early.
How much timing all has to do with what the application requires. Cars each have their specs for a specific motor in a specific body. Boat motors are installed in a wide range of boats models so the timing specs have to be set for the most extreme application to prevent any damage. This means the motors in most boats can vary a bit from factory specs and can be fine tuned to what is needed for that particular model."
 
"Just a follow-up to everyone

"Just a follow-up to everyone who gave me input on RPM issue. The major source of the problem was too stiff advance springs. The rebuilder used heavy springs due to the nature of the gas these days. Ethanol plus no lead led him to believe that stiffer springs were needed. He has rebuilt the distributors 3 times in the last 5 years and used heavy springs. The use of the digital timing light led me to this problem of only 11 -14* advance at 3000 RPM. After we told him this he put in lighter springs and the problem was 95% solved. As far as the 38*, I forgot to re-zero the meter for the final timing. Great lesson for me when using this type of light. After we reset the timing at 5* in idle with the re-zeroed light we ran at 3500 RPM and 29-30MPH and still had some throttle to go. Thanks everyone for the assistance in this solution. The boat is running better than it has in the last 5-7 years.

Take care,

Don"
 
"Thanks for all your help Jeff

"Thanks for all your help Jeff. We wouldn't have been able to solve this without your help. Unfortunately the weather has been terrible for boating the last couple of weeks but we are hoping for some nice weather in Oct. Where are you from?

Thanks again,

Don"
 
"..."Where are you from?&#

"..."Where are you from?"

Tax-a-chusetts, but don't tell anyone! I now live in PA, near Allentown, and boat on the beautiful Chesapeake Bay.

Jeff"
 
Tex-a-chusetts.....so you'

Tex-a-chusetts.....so you've lived in the political equivalent of the north and south poles!!!
 
need a lot of help!! i just go

need a lot of help!! i just got a 82 carver 33ft boat from baltimore and it is being hauled down here to tn where i live to a local lake. it has two 440 motors in it one is all apart well the heads are off. i need to know a few things?? the motors are 1975 440 b"s now here is the compression test we did on the starboard motor
150-8 4- 150
122-7 3-118 THIS MOTOR IS ALL TOGETHER AND
130-6 2-119 CAN RUN FOR ME TO MAKE THE
130-5 1-122 BOAT DRIVE

PORT MOTOR
135-8 4-130
125-7 3-120 YES U SAW RITE 30 IN #2 OKAY SO
118-6 2-30 MAYBE SOME HEAD WORK AND PISTON
130-5 1-150 WORK RING? MAYBE I'LL DEAL WITH
THIS MOTOR LATE
MY ? IS CAN I DRIVE THIS BOAT ON THIS ONE GOOD MOTOR FOR 17 MILES ON MY LAKE AND IF SO IS THERE ANYTHING I SHOULD DO TO IT FIRST BEFORE RUNNING IT }
 
I JUST NEEDED TO KNOW THAT I C

I JUST NEEDED TO KNOW THAT I COULD BE ABLE TO DRIVE THIS YACHT FROM POINT A TO POINT B ABOUT 17 MILES ON MY LOCAL LAKE . ON JUST THAT ONE GOOD MOTOR IF IF I CAN DO SO .IS THERE ANYTHING YOU ALL THINK I SHOULD DO TO THAT MOTOR AT ALL BEFORE I DRIVE IT.IT HAS NOT RAN IN ONE YEAR?
 
"I would think that there woul

"I would think that there would be no problem doing that, IF were talking about an engine that has been in working service. If you've got something that's been setting in storage for a couple of seasons, I'd definitely have a support boat available.

I feel that the real question may be, are you experienced enough to safely navigate the channels & bring a 33' boat up to dock.

Many of us have brought 'em back on one engine.

(( if your going to continue this topic, start a new post. You may get a lot more input. ))

Fred 156-M"
 
"Are you nuts!

1. You have

"Are you nuts!

1. You have no idea what work has been done. For example, is a gas line or etc loose somewhere, so it could start leaking?

2. What if the "good motor" craps out on you?

3. What about the other things you need to make a boat go that far--and that's a LONG way After all, what do you really know about that boat?

4. It's getting colder. I was out on the Chessie a week ago and it was getting really nasty!

5. Ever run a twin screw on one engine? Not fun.

My advise to you is this: Get it overland hauled, or fix it BEFORE moving it. And that includes several test rides, locally, to make sure everything is okay.

Jeff"
 
"Jeff, Tennessee, its still 70

"Jeff, Tennessee, its still 70*

Jeff, 17 miles, I assume that he is trying to get it from a launching hoist, around a lake, to a place that he can get work done. Not go bar hopping.

Jeff, for some reason, I thought it was indicated that he got a test ride in , before he bought.

Jeff, I am nuts.

Jeff, have a support boat available.

Jeff, GREAT point about checking the fuel system.

Jeff, Careful. Remember your blood pressure.

Jeff, Great to here from you.

Fred 156-M"
 
"well i would put all ne wgas

"well i would put all ne wgas in it and ck over all line and new filters and oil and plugs and anything that needs new , the boat ran last week when i looked at it however it had not run since mar. of this year ,i want to thank the man who told me to start a new post i just did thanks please go there and tell me what you all think"
 
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