Syncing the throttle levers

Newbie

Newbie

New Member
Oct 22, 2007
858
Apex, NC
Boat Info
'01 230BR
Engines
350mag B3,
My starboard throttle is off by a good inch or so (more throttle) from the port when at cruise, engines sync'd. This has always happened when I haven't run the boat in a while but has gotten better after running it for a while, within a half inch after on plane for 20 min or so. This past weekend after about 6 hrs of running it didn't change. Fuel filters are new, or maybe I should say newer, about 2.5 months, 15hrs ago. The starboard engine also acts like it is starving for fuel at 3700+ rpms and starts dropping by 2-300 rpms until pulled back to 3500 then it smooths out. Are these issues related or is there an adjustment in the throttle levers? I'm not sure if I am having to actually give more throttle to the stbd engine to keep up with the port, how would I tell if so.

My props were tuned back in March and as far as I know, I have not hit anything. My diver says everything looks good, clean bottom but a little hard growth on the running gear that was able to be cleaned off which he did early Dec. Any suggestions?
SB
 
You probably need to talk to a Mercruiser dealer on this one. I have seen one other case where the throttle levers acted like they had minds of their own. That problem turned out to be a bad fuel injector on the engine with the symptoms.
 
8.1's, Vdrive

Thanks Frank. It really is odd, especially how it appears to sometimes go away after running it for a little bit. No change in it this weekend though. I'm going back down tommorrow and plan to swap out the filters again. Those inline filters require me to bring along vicodin.

A bad injector would explain the loss of rpms that I'm getting ocassionally also. Good thing is, this 03 boat is still covered under warranty :thumbsup:
SB
 
if your props are correct then I would think an ignition problem is possible. Check the inside of the distributor caps . Also check the throttle plate for its throw ,make sure it is fully opening. Check the cable tension at the throttle body for play.The throttle is adjustable at the helm for tension to keep them set . Also make sure the prop guy took into consideration that they are v-drives and the mechanically challenged side needs to be approx..5" less aggressive.
 
Props were definitly OK. Both engines turned up to 4800 WOT during sea trial, and now full fuel 1/2 water loaded with all kinds of crap, I get 4500 WOT.

8.1's have a distributorless ignition system.. I'm going to pull the plugs to see how they look tommorrow but don't expect to see anything unusual since its an intermittent problem with the rpms. While I'm working up a sore gristle, I'll check all the throttle connections. I'm guessing its a fuel related issue myself, hopefully I'll find out soon enough.
SB
 
I'm a believer of a dose of injector cleaner once a season, which ends up to be 75 to 100 hrs for me. I use the Mercruiser / Quicksilver product for the boat, Techron for the autos. Once the cocktail is in my tanks, I try to run the boat on a long cruise and burn as much of it as I can at once...and with 8.1's that shouldn't take you too long
 
The fuel pressure regulators on my boat are controlled by manifold vacuum.

The rocket scientists that designed this system put the vacuum pickup at the bottom of a depression in the intake plenum.

At one point crud worked its way from that depression, down the vacuum hose and obstructed that control port. This prevented the fuel pressure regulator from providing maximum pressure at full throttle.

The crud was cleaned w/ WD-40 and the system works great now. All the intake components were also cleaned and there isn't any crud to be found aboard.
 
WD-40 is not for use on everything. From their website:
What does WD-40 do?

WD-40 fulfills five basic functions:
1. CLEANS: WD-40 gets under dirt, grime and grease to clean. It also dissolves adhesives, allowing easy removal of labels, tape and excess bonding material.
2. DISPLACES MOISTURE: Because WD-40 displaces moisture, it quickly dries out electrical systems to eliminate moisture-induced short circuits.
3. PENETRATES: WD-40 loosens rust-to-metal bonds and frees stuck, frozen or rusted metal parts.
4. LUBRICATES: WD-40's lubricating ingredients are widely dispersed and tenaciously held to all moving parts.
5. PROTECTS: WD-40 protects metal surfaces with corrosion-resistant ingredients to shield against moisture and other corrosive elements.
Top
What surfaces or materials are OK to use WD-40 on?

WD-40 can be used on just about everything. It is safe for metal, rubber, wood and plastic. WD-40 can be applied to painted metal surfaces without harming the paint. Polycarbonate and clear polystyrene plastic are among the few surfaces on which to avoid using a petroleum-based product like WD-40.
 
Yep

I have no idea what is in the path of the WD-40 you are spraying around in your bilge/engine compartment. So, as a word of caution, don't spray it on anything made of polystryrene or polycarbonate.

If you don't know if those materials are present in those areas, then it may be prudent not to use the product until you are able to make a determination. Of course, that is your choice.

However, others who read this post may be interested to know of where NOT to use the product.
 
Does your engine have lots of polystyrene and clear polycarbonate parts? Mine doesn't have any.

Does it make any sense to you that parts will be used on an engine that don't tolerate petrochemical products.
 
My point is that most of us may not be smart enough to determine that. So, until one has made the determination, caution would prudent.

I have no idea whether or not there is any poly-anything in anyone's engine compartment. And since I am not smart enough to make that determination, I won't be spraying too much WD-40 around mine.
 
I had the same problem with my 02' 340 w/8.1s engines. I had an engine compression test done to make sure that it was not a performance problem. It turned out that I had two bad plugs. Replaced all plugs and added some fuel injector cleaner to boot. The problem seems to be corrected.
 
After changing all the fuel filters, a high dose of Vavtect cleaner and other maint this weekend, it seemed to stop surging but the trhottle levers are still off. I was going to replace the plugs but couldn't find any. I'll try again in Feb when I get back from the Caribb. and Steamboat :thumbsup:


BTW, I completely destroyed my polystyrene cooler I keep between my engines with WD40 also. It did make it a nice liquid form that was easily pumped overboard by the bilge pump though.
SB
 
Newbie said:
BTW, I completely destroyed my polystyrene cooler I keep between my engines with WD40 also. It did make it a nice liquid form that was easily pumped overboard by the bilge pump though.
Click to expand...
Now I don't feel so bad about plumbing the outlet from my custom oil change system to a chrome-plated above-waterline mushroom-shaped thru-hull.

WD-40 was used to remove the adhesive that remained after removing the oil discharge placard.


Note, the preceding was an example of extreme sarcasm.
 
I have a 03 340 with the 8.1 V Drives and have the same issue. My throttles are about a half inch off when cruising. The engines have been tuned. Changing the props this winter going to a 4 blade prop, maybe that will help.

Craig
 
Ive tried WD on one particular item .... Still no penetration .... : (

After that there is no point ...


Rob
 
Robski97 said:
Ive tried WD on one particular item .... Still no penetration .... : (

After that there is no point ...


Rob
Click to expand...

Rob

I'll have to discuss this with your wife next time I see the two of you at Watch Hill. :smt043

Brian
 
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