penta aq125 would not start!

[2stroke1971]

<Groan>

Thought I was ready, got the big tub of water, dipped the outdrive down and proceeded to crank. and crank. and crank.
It sounded like it wanted to go sometimes, but never really caught.
I used some gas that was in a can that had been outside. A sealed can supposedly, but it had been buried in snow for 2 weeks. Maybe not a good idea, maybe bad gas.
I unhooked the gas tank (external tank not using the main tank for now)

SO later, I got some starting fluid, and it didnt even try on that...its getting spark, I pulled the plugs, they are a bit dark,but not foul... no tan deposits like a good running motor should have.

I will put new plugs in and give it another go with some fresh gas tonight.
Fun fun fun!!!

 

[Bondo]

Re: penta aq125 would not start!

Ayuh,... Fuel, Fire, Compression, All at the right Time...
You're missing 1 of the 4....

 

[captmello]

Re: penta aq125 would not start!

unless its been converted to electronic ignition, points and a condenser would be a good idea as well. Of course you'd have to reset the timing and the dwell. If you're working with worn out tune up parts, you're just making it harder on yourself.

Let us know how it goes.

 

[2stroke1971]

Re: penta aq125 would not start!

Alrighty then....

I got some fresh gas and new plugs. Cranked it, and it gave a backfire. Enough to blow my exhaust flap off. Granted, it was a little crusty anyway.
I should add it does have the electronic ignition conversion.
So...I verified the plug wiring against the firing order...heres question number one...which way does the rotor spin?

I checked the timing as far as the belt, etc. I will say this, the timing mark on the main engine pulley is pretty scant! Add some years of weathering to it, I had a hard time finding it! I wasnt sure about the cam mark at first, so I pulled the valve cover. Very nice inside there by the way. Cylinder 1 was near top dead center according to the cam lobe position....oh yeah, and the rotor was pointing to number 1 post..this gave me some assurance that this little hash on the engine pulley was in fact the mark.
Then I spotted the notch on the cam pulley.

With the engine pulley on "0" degrees, the cam mark appears to be one tooth off! With the engine pulley on 10 degrees..(BTDC I assume?) the cam mark is further off, so I extrapolated that with the cam mark right on, the engine pulley would at about 10 degrees AFTER top dead center.

Soooo....
Where SHOULD the engine pulley mark be when the cam mark lines up on the top side? I imagine it should not be at some point AFTER TDC as I am observing now.

Would a slip of only a tooth or two give me what I got? I didnt try cranking ANY more after that backfire. To hell with that! LOL...So, im not liking this belt now. I will say this, it is not as wide as the pulleys...its not like the edge is shredded or anything, but seems to me it should be wider than it is.

What do you have to remove to replace the timing belt? Ive done that on cars and vans enough, but never a penta! Is there an easy way to skip the thing back into position? Of course, it skipped for a reason, so Im thinking it would be dumb not to put a new belt on since I have to time it again anyway, right?


Starting to think the boy lied to me LOL! Im not sure this thing was running when parked!

 

[bruceb58]

Re: penta aq125 would not start!

I really doubt your timing belt slipped. You would have noticed something like that the previous time you ran it too.

What is the condition of your cap and rotor? Everything nice and dry and clean?

EDIT: Just saw your last comment about not running before. So...you have never seen this engine running before? Maybe you SHOULD check the timing belt a little. Maybe whoever replaced it didn't replace it correctly. Might want to measure compression while you are at it. I have a feeling you have no idea where the ignition timing is at. You can still check ignition timing by cranking the engine and using your timing light.

 

[2stroke1971]

Re: penta aq125 would not start!

Yeah, I should have prefaced this with that...that is Ive never seen this run. New to me boat.

No idea how old the belt is, its in fair condition, but certainly not new. no marks left, and just looks a bit old.

The more I think about it I will say that if the engine pulley mark SHOULD be on "zero" when the cam mark is lined up then relatively speaking, the cam is retarded by two teeth. that should be enough to screw me up. (Thinking out loud here)

. I guess your right, I can check the ignition timing....I would just pull all the plug wires off, because no way do I want it trying to run right now. Crnak it and check...that would give me SOME idea, although not like it was idling...Then theres the notion that I may be able to compensate and get it to run albeit a tooth off if the distributor will **** enough the right way...

Nah, Id rather just put a new belt on at this point. I may see if I can skip tha cam forward some easy way just to see if it then runs, but I aint hitting the water without a new belt.

 

[captmello]

Re: penta aq125 would not start!

I would do a compression test first. Just to see where things are with that, like Bruce said.

Have you downloaded the manual from the adults only Volvo section?

 

[2stroke1971]

Re: penta aq125 would not start!

no, i havent dl'd the manual yet. I will do that now....I may crawl out there tonight and play with it some. figure out the tensioner, maybe I can right it.

 

[2stroke1971]

Re: penta aq125 would not start!

I would do a compression test first. Just to see where things are with that, like Bruce said.

Have you downloaded the manual from the adults only Volvo section?

THANKS! I was just reading the manual....I was reading the part where they show how to install the timing belt....they say to turn the motor clockwise with a socket wrench to load the tension, etc...in any case they say NEVER to turn the crankshaft counterclockwise as you can cause the belt to skip teeth...

well guess what?
Uh huh.
Early on with this motor, it would not even crank. That turned out to be a bad relay BUT..... before I figured out the bad relay, I DID put a socket wrench on the crank pulley and I turned the motor to make sure it was not locked up. who knows which way, maybe both. hmmmm....

now how to get it back straight!

Sort of leary about moving the heat exchanger....

so the intermediate shaft is for the distributor drive? just wondering why a third mark there?....

thanks!

 

[bruceb58]

Re: penta aq125 would not start!

so the intermediate shaft is for the distributor drive? just wondering why a third mark there?....

Gets the distributor lined up.

 

[2stroke1971]

Re: penta aq125 would not start!

Thanks, Bruce thats what I thought.

I was out there last night in the dark, got my trouble light going....

I started to tear it down for replacement of the timing belt. I think to retime it Id almost have to tear it down that far anyway. Found a belt locally for 38 bucks. Just cant bring myself to tear it down and use the old belt!

Of course bolts are crappy and rusty. Broke one in the heat exchanger tank...thanks to good old aero-kroil, I got the nub out ok. I painted the pulleys and the heat exchanger tank while they are off. Gonna put a nice white stripe on the crank pulley for the timing mark.

GOt some never seez and some new bolts. Im sure there will be other issues, I cringe at removing the cooling line that runs in front of the timing area! So, depending on how much else I break, who knows I may be ready to try it this weekend.

I cant wait to see how the real volvo belt compares with this one. Previous owner was a bit creative, but so am I. The alternator on it lists for a '68 camaro/corvette! LOL!!

Got to figure out how to unload the tensioner spring...the bolt on the wheel is bad looking...gotta spray it down and let it sit a while first.

Thanks again!

 

[2stroke1971]

Re: penta aq125 would not start!

Finished taking it down enough to remove timing belt. Got it off, although a pain to get it around crank timing gear....tight fit...will be a challenge to get the new belt around that one w/o damaging it.

Saw the dimple in the intermediate shaft gear to line up against that notch in the plate behind it. I know the notch on the valve cover bit and the timing gear. How do you reference the crank end with out the pulley or plate that has the timing marks in place? I didnt see any marks on the shaft or gear, or a place to match it up with off hand.

Didnt break anything else, but the impeller seems crappy. The end of the intermediate gear drives the impeller, The gap in the cut-out in the end of the gear is much bigger than the spit thats on the impeller. Is that normal? (NOt a tight fit between the spit and the cut collar that turns it) Also, the spit on the end of the impeller shaft is corroded badly, even though the shaft itself seems nice. I will say this, holding the impeller in hand if I try to turn the shaft by hand, it feels TIGHT. I think it should spin freely by hand, what do you think?

Im gonna replace the spit....gonna see if thats a part that the place that has my belt has. Cant be much....could make one if I had to..

Timing belt is worn, the teeth have some slop..you can move the belt back and forth a tiny bit when in the teeth of the gear. theres also alot of not quite square tooth surfaces on the belt. Its toast. Also its a good bit more narrow than the timing gears, I swear its a rogue belt.

 

[sqbtr]

Re: penta aq125 would not start!

Sounds like you are missing the phenolic drive coupler for the pump

 

[2stroke1971]

Re: penta aq125 would not start!

WOW...thanks, there is no coupler in there! I know just what you mean though from my experiences with other industrial drives.

The pump was crappy! I pulled it apart and the shaft did not turn well, even without the impeller in there. I replaced the bushing in the front and that made the difference. sand blasted the housing and put a new shaft seal in. The old one was ripped up, gobs of permatex all around it. That alone would cause it to suck air....what a leaky mess this raw water cooling system was! No wonder there was an intermittant cooling issue.

Oh well, by the time I get this thing on the water, at least I will have made friends with the engine!

I have got to get the coupler for sure, now that I know there was one!...the metal spit in the shaft is bent and pitted up...should replace it as well.

Glad i work cheap. I work in the printing industry, I work on lots of equipment and I am a fair machinist. I also restore vintage motorcycles and Ive done tear downs and rebuilds on automobile engines and such, so the work doesnt scare me.

This place is a goldmine, thanks everybody! Will update...
Heres an autopsy photo:
This is whats left of the end of the pump shaft. I found a part called "Cross piece" looks like its the metal tab with a coupler on it. I guess the coupler part of this one is long gone.
http://i298.photobucket.com/albums/mm241/2stroke1971/revereware.jpg

 

[Don S]

Re: penta aq125 would not start!

The coupler is actully rubber, and that cross piece in the shaft (in your picture) is part of the coupler. #49 in the link below.
http://www.volvopentastore.com/Cool...*****.050393364--store_id.366--view_id.327255

 

[2stroke1971]

Re: penta aq125 would not start!

Got it all back together this afternoon. Tomorrow I will try again to start it up. Bought the cross piece and replaced a few of the orings in the seawater system.

The marks on the timing belt were great for lining it up, and the tensioner was ok. The fellow at the marina told me its a common thing for these...the seawater pump leaks, corrodes the tensioner, throws the belt, etc... I told him he will probably see me in there all the time, he's a penta dealer, and his prices are all the same as the official penta online store so I know what to expect.

Got to dig the timing light out of the shed. Havent used that in a long time!

Crossing my fingers!

 

[Don S]

Re: penta aq125 would not start!

Dig out a dwell meter while you are at it. the dwell is almost more important than the timing on those engines. The book says 62? + - 3?, but I have found the run best from 62? to 65? Below that, and they get harder to start.

 

[2stroke1971]

Re: penta aq125 would not start!

Don, it has the electronic conversion, so no dwell setting right?

However, lack of patience got the better of me, and I just tried it. Nothing, then another backfire that blew a hole in the storage container that the outdirve was dipped in! I am certain the engine timing is set...there was no wondering, I lined up the cam wheel with the notch on the valve cover, the secndary wheel mark with the notch on the plate behind it, and the notch on the engine pulley with the line on the blocl behind it. The belt went on with the stripes all lined up dead on with all three marks.

This is not the first engine Ive put a belt on. So . lets assume I got the timing belt on right. But, the behaviour is the same. I truly believe the old belt was off by 2 teeth, and it was worn badly so no harm done with the new belt, especially since I addressed some other problems while I was at it. However, now Im wondering what else.

As Ive read, cylinder 1 is in the front. When the engine is loned up on the timing marks, the rotor points just a bit towards the drivers side from center when its lined up on the timing mark. Thats about where the post on the distributor where the #1 wire goes in. Sound right?

I have to double check the plug wires...need to find out which way the rotor turns and then go with the firing order.

I dont have a compression tester. Wishing I did.

I pulled all the plugs, and they are all getting a fat blue spark. The accelerator pump is squirting just fine.

Fuel, fire at the right time, and compression. Compression. Oh my. Hope theres nothing wrong there. Ive got to get a tester.

Gawd.

EDIT: You know what? I could put the timing light on and pull all the wires, then crank it...just to see if its anywhere close....


Im starting to remember my experiences with my old mopars. I had lots of chrysler V8s back in the day, and there was a case where you can get the distributor in exactly backwards, 180 degrees out, and you wind up with a tremendous backfire, Ive had the spit on the distributors break off in those cases. Ive never had the distributor out, but is there a way to get these motors 180 out? HOw ould I check that?

 

[Don S]

Re: penta aq125 would not start!

Did it ever run right with the Pertronix installed? are you sure the plug wires are in the proper order. If you are looking at an aftermarket manual, some had it wrong.
Should be like this.

 

[SSSuper83]

Re: penta aq125 would not start!

Step 1..You HAVE to find Top Dead Center on cylinder 1. If I am wrong, someone correct me, but you have to find the first starting point in the ignition system.

Sounds like the belt swap went good.

It really to me sounds like the firing order/plug wires are off. You would be surprised at how many times I have singed my eyebrows off because of two plug wires being crossed..by the size of the backfire you describe..its either the distributor placement or the plug wires. Concentrate your efforts there first IMHO.