TAMD41 H-B wont start after head rebuild

Ive recently removed the head of a tamd41, decoked it , lapped the valves, fitted new injectors, sleeves, rings etc. Also ive fitted a new turbo and cleaned the aftercooler and the heat exchanger. Ive put the cylinder head back on , complete with everything else and turbo.

The engine refuses to start. I need to run a starter/charger on it to even get it to turn over at a decent-ish speed. The 12v start battery is totally charged yet hardly turns it over. The valve clearances(0.40 mm) are perfect, the flywheel hole indicating tdc to confirm num1 cylinder etc. The engine is recieving fuel, the injectors sounds like they aren't firing properly. there seems to be air? somehow getting into the lines somewhere but when i bleed prefilter and use the lift pump, not much comes out. Any uncommon places to check for air etc ? Ive tried cracking all the pressure lines at the injectors, sometimes fuel sometimes air. Also why won't the engine turn on battery power when system fully charged? Ive tried another new starter, new battery (just incase) stop solenoid seems to be operating fine. The head was off for approximately ten days. im really running outta ideas and starting to lose my rag with it . any ideas greatly appreciated.

Is oil being fed to rocker arm assy? Dry shaft slowing down rotation?

There isnt that much oil in the rockers, when i took the covers off to recheck the the clearances. Surely though you only get a decent amount after 10-20 seconds running , especially after a full head rebuild?? I'm not disregarding this , im just trying to think reasonably. Any other suggestions ??

Start by disconnecting the fuel return and let it run into a canister.
Fuel or air getting out when using feed-pump??
If pure fuel, 'blow' the the return line to the tank and be sure it is open and not blocked.
Then loosen all nuts at the injectors pressure lines.
Crank the engine until clean fuel squirts out, then tighten the nuts one at the time but KEEP ON CRANKING while tightening!!

I have tried all of the above with no sucess. after removing all air and tightening up the pressure lines it still wont fire. lossen them off and more air in pressure lines. There is also very little speed from battery although fully charged and all connections showing enough voltage. The fuel pump has just been overhauled so it cant be that and its been bench tested too. could the new injectors be any of the problem ? maybe too high a crack off pressure ? the lift pump operates fine manually and also by the cam so the problem can't lie there ..

I appreciate all the replies. Thanks

Run fuel feed AND return lines into container filled with clean diesel, manually prime the pump lever, air will bubble up in the canister, when it stops bubbles try cranking it, bleed air pressure at the injectors while cranking one by one, see if it fires.

Notorious culprit of air in lines is Racor filter, definitely try to bypass if you have one, while troubleshooting.

Are you sure starter is good? Connections on starter solenoid tight? Battery might be strong, but starter not turning enough RPM to fire.

Next step check oil for traces of coolant. If found, pull injectors and check for coolant in cylinder(s), if for some reason new injector sleeve(s) didnt go in perfectly straight they can leak coolant into cyl (sleeves are surrounded by coolant). Fluid in cyl will not compress and will bog down the cranking.

Tried all the bleeding, from a fresh can of fuel into canister. and nothing. tried injectors off pump via 6 made up pipes and eventually got them all atomising properly. so there are good and pump good too. dopnt have racor filters so dont need to try that..

i have changed starter to brand new out the box and back again after fidning it didnt make a hint of a difference..

no loss of coolant, higher oil levels etc suggesting new sleeves are fine. The manual on the engine isnt very clear on clearances and best way to set them, could this be culprit?? the whole turning 120 degrees etc aint exacrtly well described....
I do appreciate all the help , and suggestions.

Thanks

there is a special dial gauge that sits between the socket and breaker bar, to do the final cylinder head torque sequence. but if you got them very tight that should be good.

remove injectors completely and try to see if starter turns engine over at normal speed. it will not fire regardless of fuel if the RPMs are not fast enough for engine to "catch" and start. sounds like something is binding and preventing motor from turning over freely

I didnt mean about the angle gauge for the tightening of the cylinder head bolts, did them five stage , stage 1 30nm stage 2 60nm stage 3 100nm stage 4 90 degress stage 5 another 90degrees.

yeah ive had the engine turning over before ijectors were put in and its nice and fast. checked compression today and around 400psi give or take no more than 15psi??


after turning it over for 5-10 minutes , how much oil should there be in the rockers? what are the likely suspects for binding?? anythign that would have been disturbed in the rebuild?

Thanks for taking the time stringer_bell to reply and help me along the way .

You did head torque sequence properly, nice job.

OK, compression is strong, now lets figure out why motor is slow to turn over. very little oil should be in the rockers, even when engine is running it barely squirts up in there to lube, this is how its designed dont worry about that for now. If you are not hearing any obvious mechanical noises like rattle or grinding, maybe its not binding either.

Remove all 3 valve covers and try to verify that ALL valves are harmonically moving when cranking. Just last month I saw a 41 motor that snapped the camshaft after lobe #1, and only #1 valve would move, obviously motor would not start. Never heard or seen that before, so lets just make sure camshaft is rolling and all valves are going up/down

We'll get it solved, keep us informed

Is there a emergency stop lever on the injector pump . tripped ??

Well the good news is that ive got it running. The fuel pump was rechecked, all new injectors re-cleaned, and after blowing out the air lines with compressed air got her started. Think the pump wasnt making enough pressure for the new injectors perhaps...?
I also re-did the plunger stroke/angle of injection aswell.

Managed to get her nice and hot around 80degrees celcius. The only only problem seems to be slight weep of diesel around the new sleeves? more bubbles, slowly builds up under increased revs, and then smoking when its hitting the head , due to the heat. Is it possible that this will just be any diesel left in the sleeves? (bear in mind that the injectors , old and new have been out several times) It has had new sleeves, so could take a while to stop even ??

Just glad its started! but the other 41 which needed done was the exact same with new injectors, but old pump not touched and OLD injectors it fired within seconds

Just need to get the weep issue sorted now. Thanks for the help , hopefully you know about the sleeve issue too !

Amarcafina: The solenoid is the stop , taking power when you turn the key anticlockwise, or you have the manual stop on it as well. Never seen an emergency stop such as a trip though , but thanks !

Great news, congratulations. There is a trick to slightly loosen the injector hold-down bolt, and tap with the hammer at bracket side to properly seat injector in the sleeve. Try that, but be gentle obviously.

I have exactly same problem with a41 P,Had head off pistons out and checked etc,all back ok but seems to crank to slow to fire only 155 rpm .What do you think your problem was finnally down to.

Dear graemes75, / Any one ? I am considering buying an older 40 foot boat, that has 2x tamd41 They are in a very bad shape ! At least I assume they are tamd 41 there is no known year, type or engine hours It just mentions, Volvo Penta 6 Cyl, 145 Hp I encluded a pic of the engines Now I have 2 questions, A) By looking at the pic, can you confirm the type of engine B) From your info I could see that you found all the parts, where do you still get them http://www.marinepartseurope.com/en/volvo-penta-explodedview-7745630-26-19461.aspx I see only a lot of "Out of production" Thanks Tom

well, first of all tom, the engine in the photo is NOT tamd41 or any 40 series engine of any kind. It looks like tamd60 or 70 of some sort. there were no 60 or 70 series motors with 145hp though. you should definitely have an experienced marine surveyor check out that boat and motor