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1985 chevy 350 marine engine timing specs

J

jon kahler

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" Does anyone have these specs

" Does anyone have these specs, motor backfires through carbourator. if you have any other possible causes i would be very thankful.
i have replaced cap and rotor, plugs, new
carb. this was my last possibility. thanks "
 
" jon kahler
If your engine i


" jon kahler
If your engine is a mercruiser with thunderbolt electronic ignition like mine the specks are as follows:
Static timing 8deg BTDC.
Modular timing;
800-1200rpm 0
1600rpm 9to13deg
2100rpm 17to21deg
3000rpm 18to24deg
Total 32deg
Check firing order, you may heve switched plug wires. "
 
"Hello John.

If you need an


"Hello John.

If you need any other information or parts, you can call me at Dania Marine 1-800-748-7739 or email at [email protected]
Your engine problems can be related to your ignition system, timing components or valvetrain.
I will need much more information than you have given. I need to know what was done to the engine before the problem occured.

Thank you, Gabriel Acher"
 
" Backfire is caused by an ign

" Backfire is caused by an ignition problem. Check the simple things like getting NEW plugs, wires, rotor, cap. It is very possible that one of the replacment parts you purchased is BAD. Also make sure you have the plug wires in the correct position and the check the counter weights and springs in the distributor.

Going to timming without checking these items is not wise. The engine timming does not "just change". Unless you found the distributor just moving freely it should not be timming. You have not stated how many hours our on this motor. Are you talking 3000-5000 hours? It could be caused by a streched timming chain "
 
"I have a 1954 Chris-Craft, en

"I have a 1954 Chris-Craft, engine is Chris-Craft, 6 cyl flat head, single carb and coil-points-distributor ignition system.
Today I noticed that there is 'arcing' across the coil lead wire (going to the distributor). It is arcing across from the nut to the rubber high voltage wire cap.
Can you pls tell me what is causing this??
Thanks in advance.

Terry
Gananoque Ontario, Canada."
 
"Engine failures and heating p

"Engine failures and heating problems can sometimes be traced to exhaust systems, however, before OMC manifold is replaced, check the water pump flow.
OMC manifold test is done by testing the time to fill a 2 gallon container at idle speed of 550 rpm to 650 rpm.
50 to 60 seconds for 400-800 stringer series boat years 1968 thru 1986 is the test time that our mechanics use, note the water pressure should be steady, with little or no bubbles.
Intermediate housing to manifold, water pressure line is one of three lines that need to be checked this way.
******************
daisy
Used Cars"
 
Re: " Does anyone have these specs

" Does anyone have these specs, motor backfires through carbourator. if you have any other possible causes i would be very thankful.
i have replaced cap and rotor, plugs, new
carb. this was my last possibility. thanks "

Check for water in the carb bowl. A lot of the time a backfire through the carb is a lean POP caused by moisture in the fuel system. seen this a lot over the 2o years in the marine industry. If nothing has changed to the timing there is no reason to start changing stuff. moisture can collect in the fuel system over the winter season. check fuel filters. float bowls and electralasis on the points if it has points before changing expensive tune up parts.

Miloh.
 
I'd not use random advance curve specs without first knowing your engine build....... (quench -vs- full dished pistons, for example)
2-3-4 degrees, and/or 200-300 rpm, one way or the other with your TA, and you may cause detonation damage when under marine loads.

Example:
32* @ 3k rpm is very likely too much and too early if using full dished pistons (which are more prone to detonation)
30*-32* @ 3.2k rpm may be spot on for a quench built engine!

Use caution!


.
 
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Re: " Does anyone have these specs

" Does anyone have these specs, motor backfires through carbourator. if you have any other possible causes i would be very thankful.
i have replaced cap and rotor, plugs, new
carb. this was my last possibility. thanks "

What kind of motor is it? Most factory marine installs have the timing, plug and plug gap, point dwell all on a sticker on the flame arrestor or one of the valve covers. in any case I would think the local dealer would give you the specs if you have the serial number from the motor and that should be on a plate on the motor as well. I was part's MRG. for a Merc. dealer and I got those call's all the time and was happy to give the info. I could even give you a phone # if you want it that will get you the info you need.

Miloh.
 
Re: "I have a 1954 Chris-Craft, en

"I have a 1954 Chris-Craft, engine is Chris-Craft, 6 cyl flat head, single carb and coil-points-distributor ignition system.
Today I noticed that there is 'arcing' across the coil lead wire (going to the distributor). It is arcing across from the nut to the rubber high voltage wire cap.
Can you pls tell me what is causing this??
Thanks in advance.

Terry
Gananoque Ontario, Canada."

Sound's like you need to replace the coil wire. The boot is most likely broken down.

Miloh.
 
1985 Chevy 350 Marine Engine timing specs

  1. What kind of motor is it?
  2. Most factory marine installs have the timing, plug and plug gap, point dwell all on a sticker on the flame arrestor or one of the valve covers. in any case I would think the local dealer would give you the specs if you have the serial number from the motor and that should be on a plate on the motor as well. I was part's MRG. for a Merc. dealer and I got those call's all the time and was happy to give the info. I could even give you a phone # if you want it that will get you the info you need.
Miloh.

  1. As per Jon Kahler's thread title: 1985 Chevy 350 Marine Engine timing specs.
  2. Miloh, that's all fine and dandy, and very nice of you to offer, as long as you know the engine build and know that it has not been altered from OEM......, or if you know that another engine had been installed since this boat was new!
It does and will make a difference (as per my previous post).
For example, there is no way that I'd recommend a TA of 32* @ 3k rpm for a SBC Marine Engine using the full dished pistons.
The risk for ignition induced detonation is just too great with this build.
I may, however, if the build included a q/e design.

Point being, it's often more involved than just looking up OEM specs.

.
 
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Re: "I have a 1954 Chris-Craft, en

take off coil look at coil tower with a magnifying glass its cracked change the coil
 
Re: "I have a 1954 Chris-Craft, en

This thread was started in March of 2004, btw.
Apparently Jon (the OP) is long gone..... probably enjoying a cocktail somewhere out on the water!

If we have new questions, I think it would be best to start a new thread.
 
Re: " Backfire is caused by an ign

just for laughs please make sure you didnt replace long reach plugs with short reach plugs, firing up inside the plug hole will cause backfiring aswell
 
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