Volvo Penta 5.0 GL-B does not go properly

[Danmarine]

Hello everyone.

Hope it's okay to write in here, if not admnin feel free to delete the post!

We have a problem with a Volvo Penta 5.0gl-b. An acquaintance bought the engine a few years ago and has now got it started. To keep it short, the usual things have gone through. New oil, new impeller, new fuel, new fuel filter, new oil filter, etc.

The problem is this:
The engine may be a little difficult to start when it's cold - but once it's started, it runs perfectly at idle. Once the engine has warmed up and you turn it off, is it difficult to start again?

Another problem that probably has a connection with the previous one, is that when the engine is running and you put it in gear for sailing, then the engine almost dies? It has difficulty pulling (lacks power) and it smells of unburned petrol?

We did a compression test and it was fine. We therefore suspect that the ignition is completely wrong or that the carburetor is faulty?!

But how and where we should we start - we are a little in doubt. We would really like to have set the ignition, so we are sure that it is correct, but on the flywheel there is unfortunately only one mark / line and no degrees or numbers? We assume that the mark matches TDC for cylinder 1 - but we are not sure?

At the same time, we are in doubt as to whether the ignition on the distributor goes clockwise or counterclockwise? In terms of adjusting it? :=/

We have made a sketch of the engine, seen from the air and with the idea we think the ignition should be - but here you are very welcome to correct us if it is wrong. Se pict. Firing order

In addition, we also accept good ideas for how we possibly can turn the engine - now that there is not exactly a flywheel you can just put a top on, as there is a seawater pump?

As I said, it idles well and it can also easily give gas - but as soon as it has to do something (sail), it coughs and is close to dying ??

Hope someone can be helpful and possibly. can guide us closer to a conclusion

Great day to u'

 

[QBhoy]

I’d firstly suspect that auto choke

 

[dubs283]

I’d firstly suspect that auto choke

Would account for the rich running condition, though doubt the engine would idle well which OP says it does. Need to verify operation nonetheless.

Would definitely change out the nasty dist cap/rotor along with plugs, wires, and fuel filter(s)

OP, in order to properly check/set timing you'll need a jumper harness for the ignition module with 12+ volts applied to the jumper wire and either place an index sticker on the balancer or use an advance timing light

 

[Danmarine]

Thanks for the feedback.

Yes, the distributor is probably not completely new - so it may. well be it needs to be replaced.
I have an inductive timing light and was hoping a bit that it could be the ignition that was to blame for it all? But they do not sound like it.

If I need to adjust the ignition, do I need a jumper, like the attached picture? But think someone has written something about that you can put a thin thread in between the pins (can not find the page right now) But otherwise I must have got a jumper.

At the same time, we can also leave it in the position it is now. It wants to start, it can also idle, it also wants to take gas - as long as you are not engaged. But as soon as you engage, the engine starts to shut down.

So now that QB writes that it may also be due to auto choke - so I wonder if we should also have renovated the carburetor?

But right now, the engine is really hard to start and the batteries are also getting tired ....

 

[Scott Danforth]

go thru your carb and rebuild it. by your description in post #1, it sat for a while. the fuel that was in there, has now turned to sludge from sitting and gummed up the circuits.

its a holley 500 CFM 2300 2-barrel. to do a proper rebuild should take someone experienced about an hour total time, 24 hour duration

pull carb and dissassemble - 15 minutes
soak carb parts in carb cleaner overnight
scrap any remaining gasket bits and prob all the passages with fishing line - 15 minutes
assemble carb and set float height, etc - 15 minute
install and adjust carb - 15 minutes

 

[Danmarine]

Hi Scott.
Thanks for the feedback. So you mean when the engine can idle well and can easily take gas uncoupled, then the problem is probably the carburetor?
As mentioned, it is only when the engine has to perform when sailing that it almost dies.

I have at least disassembled the carburetor now, bought the overhaul kits for it incl. new nozzle tip.
I even have an ultrasonic container with the right liquid in it. Then I have to try to get it cleaned well and thoroughly and check all holes - here I actually also have a needle set for cleaning nozzle tips and very fine holes.

Before I disassembling the carburetor, I tried to start the engine again, but without success. Now the batteries are also so flat that I have to recharge them.

If the ignition is to be adjusted subsequently, as I understand it, a jumper must be used for the distributor. In addition, I could use a paper or similar you could stick on the flywheel, so I could set ignition degrees - is it possible to download or get one somewhere? I have a regular ignition gun for this and then I also have an advanced ignition gun.

But now we can just try with the carburetor first.

 

[kenny nunez]

With a test light or volt meter check to see if the ignition “by pass” circuit is working. Probe the + or bat side of the coil when in cranking mode. There should be full battery voltage at that point. No or low voltage is a symptom of hard starting. If so then the problem will be caused by the starter boost relay. Volvo usually has a square Bosch relay. It will have a 16-18 gauge yellow/red and a 10-12 gauge Y/R wire, the larger one goes to the main starter solenoid. There will be a purple wire which goes to the + bat side of the coil along with a black ground wire.

 

[Scott Danforth]

here I actually also have a needle set for cleaning nozzle tips and very fine holes.

do not stick anything metal in the passages other than maybe a piece of soft copper wire. the bowl, metering plate and throttle body are made of zinc and easily damaged.

do not use simple green cleaner or bleach for the same reason.

 

[Danmarine]

Hi Kenny.
Thanks for the information. I will try to take a measurement on this. I assume in the attached image that the purple wire for the coil is + (plus) and the gray wire for the coil is - (minus). So I have to use a multimeter to measure the voltage between purple and ground to check if there is enough voltage when turning? And if there is not a suitable voltage here, then I have to try to measure on the relay itself?
Finally, correct me if I have misunderstood you. Please see attached picture

Scott:
Thanks for the advice. I stick to a fishing line or similar and of course avoid the use of hard cleaners and machines

 

[kenny nunez]

Yes check the purple wire. Good luck.

 

[Danmarine]

Hello everyone.
Now I have separated the whole carburetor and cleaned it, put new gaskets in, new pump, adjustet etc.

Mounted carburetor on the engine. Measured voltage to coil, 12.6 V so that's fine, right?

Tried to start the engine - without success.
Tried to put cylinder No. 1 in TDC, turned back slightly BTDC maybe 6 deg. Adjusted distributor so that it is ready for ignition on cylinder no. 1 and tried to start again. Unsuccessfully!

Disassembled spark plugs and kept them out in the open to check for spark - there is almost no spark, so now it is almost only the distributor and ignition module that can be the problem?

There are new spark plugs on. So thinking of getting new power distributor, ignition module, coil, rotor and ignition cables. Have a new coil right here next to me.

But I have a bit of a hard time getting this model (see attached picture). Can I buy another model, a similar one or search under other names?

Volvo Penta have one in stock, but you have to bring the big wallet with you ;D

Is there anything I have overlooked or that you think I should try?
Finally, it should be mentioned, (although I know there are divided opinions about it), but tried starting fluid - even this could not start the engine!

 

[kenny nunez]

The voltage at the coil is 12volts while cranking the engine? There should be a blue spark at least 3/4” from the coil wire to ground.

 

[Danmarine]

Hi Kenny.

Thanks for the feedback.
Well you just mentioned it. When I measure with ignition on and only, then there is 12 V. But while the engine is cranking, it drops to 8 V.
But thought it was probably due to evenly large power consumption, for starter, relay, pump, etc.
But could it be a problem? - maybe I should take a closer look?
In that case, it must be the solenoid?

There was no clear blue spark, just a small white flash of light ...

Thanks

 

[Danmarine]

Arh, sorry Kenny!
I did not see the detail in your previous message - you write that I have to measure while the engine is cranking ... ups

Like I said there is 12V with ignition on and if I am cranking the engine it drops to 8 V... :=)

In that case, it's probably due to the starter boost relay, just like you mentioned.
Then it is the relay, we possibly must try first?

By the way, the starter does not crank the engine very fast either and has also started to go out of engagement during turning ... Despite the fact that the batteries are fully charged again?
We've probably had killed the starter now ;D

 

[kenny nunez]

Get a jumper wire and connect the + battery to the + side of the coil then spin he engine and check for the spark. If the spark improves then try starting the engine, if it starts disconnect the jumper wire. It will probably be the main starter solenoid. Measure the voltage at the purple wire on the outboard side of the main solenoid when cranking. There must me full battery voltage at that point when cranking.

 

[Danmarine]

Now I just tried again.
Measured the voltage on the coil, with ignition set on and there was 12V. Then tried to measure while the motor cranked, it drops to 7.5-8V - measured on the cable that goes to the coil with supply.

Then tried to swap around the start relay and fuel relay (they are the same, both just a fairly ordinary working relay). After replacement, the engine would like to crank faster than before, but still no starting. Unable to start engine with starting fluid...

Then measured on the purple wire on the solonoid, the voltage also drops here to 7.5 - 8V while i'm cranking the engine.

Did not check if the spark of ignition got better - a little awkward when there is only me for it and when the other things also appeared, as you mentioned - which is not good?

As written earlier, they had got the boat in the water. Started up and put in gear where it almost went out - but if you just gave a little more, then it will still go on.
But they sailed very slowly, got it too much it would die. They therefore sail quietly in port and before they get completely in place, the engine died ... And ever since, it has been impossible to bring to life!

I get a headache from it

 

[dubs283]

Sounds like your battery is toast. Have you load tested it?

Good idea to replace the dust cap/rotor, they look nasty

 

[Danmarine]

Hello everyone.
thanks for all the suggestions so far.

Yesterday I tried to change the distributor cover, rotor and it was also needed. (see attached).

Unfortunately, there have been no signs of a start yet.
But I have discovered that there may be something teasing - if I peel the supply from the coil up to the distributor cover (the cable that sits in the middle) and put it loosely on the block, somewhere against a good ground connection - then there will be no spark?
Then tried to disassemble spark plugs on cyl. 1 and tried the same, no spark?

The distributor and the shaft for this have been up, made it all clean. Clean the shaft at the top, with sandpaper, where the rotor should sit. Replaced rotor with a new, replaced ignition module, replaced cover. Then turned engine to TDC according to cyl.1 in compression stroke, set a few degrees before TDC. Adjusted distributor shaft and cover so that cyl 1. is on ignition and yet nothing happens ....

Checked kill switch and it is also ok.

Now I am trying to get the batteries recharged (they are brand new). The motor is quite difficult to pull around - but the cables do not get hot.

Also has measurements from the battery plus (+) and to the ground (-) on the engine and several different spot and it also looks good.


I'm seriously completely out of ideas. Why could the engine start, sail (well enough with reduced power), go out on its own on arrival and just like that it has been impossible to get started .... What happens?

Everything seems to have been checked or replaced / replaced with new / other parts. Fuses checked, connections checked, etc. etc.

Could try to throw some new spark plug cables on. But think it's a little wild if all 9 cables break at the same time?

My last deposit is that if the batteries are getting tired and the engine is spinning too slowly, then maybe not a spark is formed? It's not something I know anything about, but can it also be a problem?

Hope someone can give me a few new clues or hints

Thanks

 

[jworth21]

I had a car once that died while driving down the road from bad wires and plugs. Wouldn't have believed it had it not happened to me. Started fine 20 minutes earlier. How are your engine grounds? I know you checked voltage but if you don't have good grounds then that resistance may not show up into you're trying to pull more amps through it. Just a cheap easy thing to check

 

[Danmarine]

Hi Jworth21
Sounds like you've experienced something similar.

As mentioned, I have measured on the engine over several places to check for connection. Have had the plus (+) and minus (-) cables off, given them a turn with sandpaper, cleaned the block where the ground cable is mounted. Unfortunately, that has not helped.

Now I try with freshly charged batteries, new spark plugs and spark plugs (the current spark plugs are also new) and if that does not work, I try to mount starter cables - maybe the fault is further inside the cables and not in the pole shoes themselves.

As mentioned, I adjusted on the ignition and at the distributor (had the shaft removed). Now I know that if I have to adjust the ignition during operation, I need an advanced ignition tools + a jumper for the distributor (volvo tool) ...
But come to think of it, it's not like if I fiddle with the distributor with the engine off, it's always trying to find its way back to its proper place? Ask stupid enough, but just want to be sure there is nothing that can **** it up?

Thanks