Should I be worried about cracks in a new belt?-gctid820391

[tdcooper99]

A few weeks back I posted about my idler pulley failure...the tensioning pulley for the belt that drives my raw water pump.I've been having issues with a squealing belt .... hard to tell which one, but I am pretty sure it's the belt I replaced along with that idler pulley when I had my issue. Bought some belt conditioner and gave it a few shots... which solved it temporarily... and I am fairly certain the belt is tensioned correctly. I really don't want the thing strung so tight I could play an Eddie Van Halen guitar solo on it, but it's pretty tight. It does stop squealing once it gets warm... but still doesn't seem right that it squeals at all.

Today... I'm cleaning my bilge and I notice the brand new belt (literally maybe 6 hours on it) has cracks in it. Is this normal? I am starting to wonder if my raw water pump is really putting some strain on that belt? See pic:

[Pcpete]

That there just isn't right. Finding the cause is a guessing game that would run from a belt that was produced twenty years ago to a bad batch. I would clean the pulley faces where the belt rides then install a new belt and buy a spare. I suggest going back to the newest mercruiser labeled part number. For that you will need the engine serial number and model. Pick your search engine and start with mercruiser parts. Find a site that has the schematics and look up your part. Then you can go shopping at a napa, Canadian tire, etc.

Really clean pulley faces are going to be important.

[tdcooper99]

"Pcpete" post=820398 wrote:
That there just isn't right. Finding the cause is a guessing game that would run from a belt that was produced twenty years ago to a bad batch. I would clean the pulley faces where the belt rides then install a new belt and buy a spare. I suggest going back to the newest mercruiser labeled part number. For that you will need the engine serial number and model. Pick your search engine and start with mercruiser parts. Find a site that has the schematics and look up your part. Then you can go shopping at a napa, Canadian tire, etc.

Really clean pulley faces are going to be important.

Ok, I'll do some pulley cleaning. Batch produced 20 yeasr ago doesn't seem realistic... but the spare I bought at the same time had to be ordered in as they only had one in stock when I needed it so it's more likely to not be old. Maybe I switch to the spare, order 1 more and see what happens.

[2850Bounty]

Steer clear of the BBQ Pork V-belts. I would take it in and match it up to a US made V-belt.

Although this is likely not causing the belt issue, I also agree with Pete......, the pulley V faces are rusty and should be cleaned up.

[green650]

Switch to a crank driven pump and you won't need that pesky belt anymore. And you'll get rid of the troublesome mercury water pump. Yours should be easy since you're non MPI and have the centering pins on the crank.

[2850Bounty]

"green650" post=820459 wrote:
Switch to a crank driven pump and you won't need that pesky belt anymore. And you'll get rid of the troublesome mercury seawater pump.

[color]blue wrote:
[size]5 wrote:
100 X's Ditto and Amen Brother![/size][/color]

[tdcooper99]

"green650" post=820459 wrote:
Switch to a crank driven pump and you won't need that pesky belt anymore. And you'll get rid of the troublesome mercury water pump. Yours should be easy since you're non MPI and have the centering pins on the crank.

So what would drive the fuel pump then? Would I have to switch to an electric fuel pump?

[Ruffryder]

Pulley surface is about the worst I've seen.

Yes , you will need to convert to an electric fuel pump feeding it through the oil pressure SWITCH per USCG regulation.

[2850Bounty]

Clarification ......... the electric feel pump would be powered by a relay that is triggered by a N/O low oil pressure switch.

.

[Ruffryder]

Not necessarily...

FYI, NO FUEL PUMP RELAY used for electric fuel pump driven Mercruiser CARBED engines.

One less device that can go wrong.

Rick, we went over this topic a few yrs ago maybe.

[2850Bounty]

Joon, do as you wish...... I will always incorporate a relay.

With a relay, the start-by-pass circuit will not be able to pose any potential feedback issues.

.

[green650]

"tdcooper99" post=820483 wrote:

"green650" post=820459 wrote:
Switch to a crank driven pump and you won't need that pesky belt anymore. And you'll get rid of the troublesome mercury water pump. Yours should be easy since you're non MPI and have the centering pins on the crank.

So what would drive the fuel pump then? Would I have to switch to an electric fuel pump?

And that's another reason to get rid of that belt driven water pump. The combo water pump/fuel pump is known to leak.

http://forums.iboats.com/forum/engin...mp-maintenance

[Ruffryder]

Not as I wish,

That is how high paid Mercruiser engineers designed to be....the start by pass circuit, when it's fed thru the starter solenoid, I do not see any potential feed back issues.

[builderdude]

Me thinks If the PO's raw water pump/fuel pump is working as it should and his only issue is his cracked/squealing V-belt then he should grind/sand the rust off the pulleys and install a quality V-belt and be on his way

[2850Bounty]

That is how high paid Mercruiser engineers designed to be.... the start by pass circuit, when it's fed thru the starter solenoid, I do not see any potential feed back issues.

The "start-by-pass" circuit is initiated by the starter motor's solenoid circuit........... it is not fed through the starter solenoid.

LOPS = low oil pressure switch.

N/O = normally open.

OK...... for those of us who don't know and/or may not understand the electric fuel pump and the USCG requirements:

In the event of engine trouble that would disrupt operation..... the fuel supply must stop.... just as it would with a mechanical fuel pump.

We use the absence of Engine Oil Pressure and a N/O LOPS to achieve this.

Engine quits operating..... oil pressure goes to zero..... LOPS contacts open...... fuel pump loses electrical power and quits pumping fuel.

If a fuel line had been severed, a fire may have been averted.

However, in some cases whereby the carburetor bowl may be low on fuel, the N/O LOPS needs to somehow power the fuel pump prior to the engine achieving oil pressure...... correct?

It can not do this while the contacts are open........ correct?

While there is no oil pressure present (i.e., LOPS contacts are still open), the starter motor's solenoid triggering circuit simultaneously and momentarily triggers the relay.

In other words, this circuit circumvents (i.e., by-passes) the "open" contacts within the required N/O LOPS.

It does this only while engaging the starter motor.

This is what we refer to as the "start-by-pass" circuit.

The now momentarily triggered relay then operates the electric fuel pump and brings fuel into the carburetor bowl.

Once the engine starts up, oil pressure is achieved and the N/O LOPS contacts become Closed!

Once these contacts are closed, this circuit then continues to trigger and hold the relay closed causing the fuel pump to continue operating.

It's actually very simple!

And Dave.... you are correct.

Repair the pulley and replace the V-belt and he should be good to go!

.