Low speed problems with 85HP Chrysler Charger

[Charger 85]

We are new boat owners and bought a 78 Chrysler 15 ft Hydra V boat with a 85HP Chyrler charger outboard.
Last year we fought with it with the ethenal fuel which caused a good deal of problems. We have since been going to our bulk fuel distributer and getting non ethenal fuel.
Current problem is that it will not idle and tends to die at low speeds. Also, going into reverse (again at lower speeds) it kills out.
Runs like champ at full throttle.
Thanks for any ideas you have.
Ryan

 

[Dave K.]

Re: Low speed problems with 85HP Chrysler Charger

yeah, most o/b's run better at higher speed. had the same problem w/ my '84 some years ago. first: ck your idle screws on each carb. factory on mine is lightly seated then back out 7/8ths. that pretty much solved my problem. sounds to me like your carbs could be dirty or may need a rebuild. mine fortunately didn't. i can't remember but i may have run a fuel additive thru a tank of gas & it never hurts to run a can of stabile thru as well. you can also put a new fuel filter in although i'm not sure that will help the reverse & low speed problem.

try adjusting the carbs first. then look to clean or rebuild if the problem continues. BTW/ i've heard a rebuild is easy & the kits are everywhere. plenty of guys here can help you step by step.

 

[Charger 85]

Re: Low speed problems with 85HP Chrysler Charger

We will have her out this weekend and give that a try on the idle ajustment first, If that doesnt go well, Then take the time rebuild the carbs myself. I had someone else do the job for me last fall after the ethenal problems.
I will report back to the findings.
Thank you.

 

[john from md]

Re: Low speed problems with 85HP Chrysler Charger

How about some additional information. When was it last tuned up? What was done to it? Do you have an internal fuel tank? What is your compression? Have you decarbed the engine recently?

Mechanics need a history on the device that they are troubleshooting or you will just be getting a shot in the dark.

John

 

[Charger 85]

Re: Low speed problems with 85HP Chrysler Charger

John,
We have not had it out yet and to answer the questions the best I can is that we bought the boat last spring and being the novice I should have taken it out on the water first before buying it. We had problems with the fuel from ethanol mix which we found out not to run in two strokes I bought an additive and no avail still ran badly no mater what speed. Took it in to the local guys here at the boat shop and they did a tune up for me on it new plugs new hoses cleaned everything out lots of gunk in the carbs from the previous owner.
They did do a compression and ignition test and found it satisfactory and by the time we got it back it was too late to run so I cleaned out the fuel tanks and which are two external type, put in the shed and waited for spring. we took it out and the above was the way it ran excellent at higher speeds boggy other wise I should mention lots of smoke at the lower speeds also.

 

[john from md]

Re: Low speed problems with 85HP Chrysler Charger

I believe your problem may stem from the engine drain system not working properly as well as normal carbon and varnish build up.

I hope you have some kind of mechanical ability cause you will need to get dirty and turn wrenches to fix your problem.

First thing I suggest you do is clean out the cylinder drain system as the reeds may have carboned up. On that engine, the cylinder drain system is under a plate on the right side of the engine. It is a vertical cover about eight inches long. It has screens and reeds that need to be cleaned. Also, the hose at the bottom goes to the intake manifold and that too needs to be cleaned. I would use spray Seafoam which is called Deep Creep. It breaks down carbon and varnish. I doubt that you can get gaskets for that engine so just use Blue RTV when you reassembel the drain housing. DON'T damage the reeds! Just spray them and do not scrub them as you may not be able to get new ones.

Next, I suggest that you follow the decarb procedures that are listed under the FAQ in the beginning of the Repair and Maintenance section of iboats. It is on the second page I believe.

After you do this, you will have to adjust your idle mixture and idle speed. Remember to adjust the idle speed while tied securly to the dock with the engine in forward. It should be set to 750 RPM.

This should give you a much better running engine as long as it doesn't have any mechanical problems.

BTW, you can burn 10% ethanol as long as you have changed your fuel lines to ethanol resistant. Since you have external tanks, you can drain them in the off season and you don't have to worry about phase separation. I would recommend backing off your timing to 30 deg before top dead center as today's fuel is not the same as that made in the seventies and eighties.

Regards,

John

 

[Charger 85]

Re: Low speed problems with 85HP Chrysler Charger

We had it out tonight,the adjustment helped but still slightly doggy and smokes like a fiend.
John,
Yes I have some mechanical ability. Just not with two cycles.
that is why I took it down to the guys at the shop.
But I think from what you are saying this has been over looked and I will need to do it, So with that in mind I will order a book for the parts breakdown and copy this post look over the FAQ on the decarb and start in.
One last question I have not heard of Deep creep where do you pick that up from????
Thank you!

Ryan

 

[john from md]

Re: Low speed problems with 85HP Chrysler Charger

Ryan,

If you can turn wrenches, two strokes are a breeze as they are super simple. No cam or valves and their associated complexities.

Deep Creep is the spray version of Seafoam. Both are available at most auto stores and some Walmarts. I know for sure that Advance Auto has them. Of course you can always get them at a boat store like West Marine, but they will be more expensive there.

When you buy a book, get a Clymer book if they have one for your motor. They are better than Seloc books but Seloc will get the job done.

John

 

[Frank Acampora]

Re: Low speed problems with 85HP Chrysler Charger

If the compression is OK, and the engine runs well at high speeds, do not bother with the Sea-foam or Deep-Creep. I have seen instances where these treatments have resulted in engine damage to older Chrysler engines. There are times where these treatments may be helpfull, but in this case, I don't believe it will help and it may harm your engine. I am not a fan of these compounds and do not use them in my engines. However: It is your engine and your money. "You pays yer money, you takes yer choice."

Low speed needs to be 700-750 RPM IN GEAR, in the water, about 1000 in neutral. Buy a Clymers and be certain the carbs and timing are synchronized. Full throttle timing can be 32 degrees advanced, but 30 degrees is a bit safer.

Lastly, these engines are NOTORIOUS for fouling plugs. The spark plugs are surface gap and dead cold. Because of the ignition system, once fouled, the first symptom is hard starting or lack of reliable low speed/idle while high speed is unaffected. Do not try to remedy this by using a hotter or bent electrode plug, this will cause engine damage. Clean the plugs or replace them. Use only Champion L20V or UL18V Or NGK BUHX.

These plugs are very simple to clean with a green scrubbing pad (Skotchbrite). Just get it into the gap with your fingernail.

Please do not mess with the low speed mixture screws in an attempt to improve the idle. Setting them too lean will improve the idle, but will result in melted pistons at high speeds. On your engine 3/4 to 7/8 turn out from lightly seated is the absolute leanest you wish to go.

 

[Charger 85]

Re: Low speed problems with 85HP Chrysler Charger

I don't have any experience with these engines and I am at this moment going to order a Clymers manual and look it over when it comes before doing much more.
I will head your advise and make an a decision from there.
One last question can the reeds be dipped and cleaned in Carb cleaner to clean the carbon off if needed???? I did not want to spray the cleaner in or on the engine.
Again thanks to John and Frank for you your advise.

 

[Frank Acampora]

Re: Low speed problems with 85HP Chrysler Charger

I do not think you will need to treat the reeds. In all the engines I have repaired, I have never seen a ste of reeds either varnished or carboned. I have seen the aluminum Vee blocks corroded and the reeds rusted, but if your engine is running well at high speeds I don't think you need to worry about that.