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Aq131d cylinder head question

El,

My fuel is probably bad, will be hooking up to an external tank this weekend to test. Also, my carb is a complete remanufacure which I recently purchased from a dealer in Florida. Not from Ebay. I took engine apart again to recheck timing and discovered that the cam was off one tooth (dot was one tooth past the groove foward) probably because I forgot to take the slack out first. Secondly, I was a bit confused about cam timing and ignition timing. I am straight I believe on that now. I had all the marks for the gears lined up correctly and then put the cover on and the harmonic balancer. What I was confused about was that if the engine was at TDC why was the crank pulley mark lining up on the 10 degree mark on the timing cover. Someone told me that I need to align all the timing marks on the gears first, then pull the dist. out and rotate the balancer until the mark on that (the one the timing light hits) lines up with the zero degree mark on the plate. This is actually TDC (at least that is what he said) then put the dist back in and align the rotor to the number one cylinder and adjust once it starts. I will be deep into this engine this weekend as I am determined not to miss another season on the water because this engine is finicky. Thanks again for the help. I will update later this weekend on whether or not I am successful. The coil is correct, cap and rotor are new. Probably could use new wires, although they appear to be fine, but I did not put them on and have no idea how old they are or when and if they were ever replaced.
 
How dumb is dumb? Well drained entire fuel system refilled and reset cam and then ignition timing. Started right up idle is high. About 2000 rpm. Checked with light. It was at 40° turned the dist mark moved to 20° then stalled. Should I adjust idle then rotate dis? Ran smooth and sounded great. But I still think I am off. The fuel was probably my issue. Almost there I think
 
It definitely sounds like the gas was bad, but I don't think you have installed the timing belt correctly.

TDC stands for Top Dead Center. To time the gears correctly, you have to place #1 piston in the TDC position. Then the mark in the crank pulley must align with the zero mark on the timing cover. If you want to be 100% sure, remove the timing cover and make sure the notch in the outer guide plate in the crankshaft gear is aligned with the mark on the housing. That will ensure you have #1 piston on TDC. Then proceed with installing the timing belt. The whole process is described in the pdf version of the OEM manual, pages 71 & 72 (points 183 to 190). Then install the distributor as indicated on page 93 (points 295 to 300).

Once you have done this correctly we will talk about adjusting the ignition timing and idle speed.
 
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El, I have all three gears aligned to their respective marks. The cam gear is aligned to the notch in the valve cover, the gear near the dist. is also aligned to the notch in the guide plate on the block and the crank is aligned to the mark on the block which corresponds to the notch in the outer piece of the crank gear. However, once i place the crank pulley on and then the timing plate, the mark on the pulley lines up under the 10 degree mark. I read the following on the volvo forum:

The recent struggles with my 740 revealed how the crankshaft pulley can degrade without obvious signs and how this degradation can affect drivability, curb idle, ignition timing and proper indexing of the crankshaft and camshaft sprockets during a timing belt replacement.

The outer edge of the crankshaft pulley has the ignition timing mark etched on the surface. This mark is used to set proper ignition timing and to initially index the position of the crankshaft during timing belt replacement. The crankshaft pulley is also a vibration dampener. The center hub is connected to the outer pulleys by a molded rubber donut in between.

This design creates a problem that will manifest as the crankshaft pulley ages. The accessories driven by the crankshaft pulley (alternator, water pump and air conditioning compressor) place a constant load on the rubber donut, trying to restrict the movement of the pulley. The center hub has a constant load from the crankshaft in the opposite direction. When, not if, the rubber donut deteriorates, the pulleys, with the timing mark, will rotate on the donut and move the timing mark with respect to the center hub, advancing the timing mark relative to its proper position. There is no way to verify proper timing mark position without removing the crankshaft pulley from the engine and either comparing it to a new one or measuring the position of the timing respective to the keyway slot in the center hub.

Poor idle and poor drivability issues occur if the timing mark begins to advance from its proper position and the ignition timing is readjusted. If the timing mark has slipped from 1 to 18 degrees and the timing is readjusted in this condition, the ignition timing will actually be retarded and the engine will still run, but poorly

I'm wondering if tthis why my crank pulley mark is lining up under 10 degrees? Anyway today i decided to try again and i ensured all marks were correct. I had the #1 piston at TDC by placing a hose with a spark plug type adapter on the end and threaded it into the #1 spark plug hole. Manually turned the crank pulley until I felt the pressure pushing out the hose. The cam and all other gear marks were properly aligned. I then rotated my dist until the rotor pointed to the #1 plug wire (was just before actually). This allowed the engine to start. I then moved it counter clockwise until I could get it to run smooth, never really did though unless I gave it throttle. but I think it is there, just need to figure out how to get it to stay running, which i think could be the carb adjustment. I am running a hotspark electronic ignition as well if this matters any. The carb is new, bought it from flying fish carburetors in FLA. I appreciate the help. Another post on the volvo forum told me that the B230 engine should be at 12 degrees btdc. The manual states 6? May be the difference due to the type of cam in the boat vice auto. again though if I throttle slowly, it dies, if it is done quick it takes off.
 
I think you have answered your own question regarding why the marks do not line-up. A new vibration damper would prove the point, but somehow I think you will not want to go there when you see the price (and that's euros, without including VAT or shipping!!!). Your best bet would be rescuing a good used one from an old AQ131. You can always draw a new mark on the one you have, but you never know what kind of no-good will that old vibration damper of yours be up to.

http://www.marinepartseurope.com/en/volvo-penta-explodedview-7744650-21-18780.aspx

When it comes to ignition timing, my main concern would be that at 4200 RPM or higher the advance does not exceed 36º. But again, to verify that you need a reliable mark on the pulley.
 
rdengil1 said:
advance auto parts has one for 85.00.
Click to expand...

That sounds far more reasonable. However, I haven't done a cross-reference of that particualr part with VP, so I am not 100% sure that the marine and automotive vibration dampers are identical.
http://www.autopartscanada.ca/ShopB...al&subcatid=240182@@Crankshaft Pulley&mode=PD

I remember that the B21 the pulleys are different for automotive and marine use, but they are just pulleys.

If everything else fails, there is one genuine VP damper (used) on eBay for $199.

http://www.ebay.ca/itm/Volvo-Penta-Vibration-Damper-855476-AQ125B-/220803032132
 
Rock auto.com has one for 65. I also have the B230 block, not sure if it makes a difference. But I may just go ahead and try the new pulley, can't hurt.
 
ok, bought the new pulley, laid it on top of the other and...what I expected...wasn't what I got. Both lined up the same, so the pulley isn't off at all and the cam timing is perfectly set...so I guess the crank pulley when all is good is supposed to have the timing mark line up under the 10 degree mark. So pumped the throttle a few times and started it up, ran and chugged a little, the I moved the dist, smoothed out and then died. So I did it again, got it running and the timing mark indicator using a strobe timing light was at 6 degrees, but it started to die again. I gave it throttle quickly because if I don't it dies as soon as the throttle moves. ran it up to about 2500 rpm and the degree mark was at 15 degrees, moved it to 3000 rpm and it was at 20. It appears the advance is ok. At 2500 rpm, she was smooth and sounded great, as soon as I back down she idled ok for a few minutes, then as I was about to adjust the idle screw it dies. Cranked back up and tried again, same thing, adjusted the air screw by seating all the way, the backing out two turns, no difference, seems that at low rpm or starting, I can't keep it running. I am about to give up and put it for sale, she is good at her game and I just don't seem to be as smart or able to get ahead.
 
I do, but there are only two screws, the one on the linkage for the throttle and the another one on the front of the carb facing the cylinder head. its a large head screw and has a spring this is what the book says is the old style air mixture. It is turned two turns from fully seated.
 
I have considered the engine doesn't like me. I am going to recheck the carb base plate to ensure that is on correctly. Then I will remove the linkage and try that as well. What I don't understand is that the workshop manual states to align all the marks for the toothbelt installation, which I have done numerous times. Then later in part 5c para. 295 it states the following:
Turn the crankshaft to the firing position fornumber 1 cylinder. Check to make sure that thecamshaft cams for number 1 cylinder are pointingaway from each other and that the pulley marking is​
indicating ‘0’.


Put on a new gasket and install the valve coverand the plate for the belt marking. Make sure thatthe belt marking coincides with the recess of the​
plate. Adjust if necessary.

Then put the dist. in. (properly aligning the rotor to #1)

My problem is that when I put all the marks lined up, the pulley is at 10 degrees when I install the timing cover. I bought a brand new pulley, not used, and it lined up the same.
Am I missing something here? This is the question I haven't had answered and cannot find anywhere. When the gears are all in alignment, I thought his should be TDC indicating 0 degrees, am I wrong? I just line up the cam, crank and intermediate gears to the respective marks and then the belt with its corresponding marks, once that was done the pully will only lock in one way and the mark indicates 10 degrees. Probably doesn't matter anyway because if in fact the gears indicate TDC at 0 degrees, then the pulley mark should only be used to dial in the base timing and advance. So if it indicates 10 degrees BTDC at 0 degrees (by the gear settings), and I need 6 degrees BTDC with 900 rpm, then I would actually need to see the timing mark at 16 degrees BTDC with the timing light (at least this is what i think it should be if the pulley is off 10 degrees). It did run smooth at 15 degrees BTDC but the rpm was around 2500.
 
So if I understand what your saying...remove the timing belt and move the crank pulley to the zero degree mark (ignoring the mark on the block and the gear). Then reinstall the belt with the cam gear dot lined up to the notch in the valve cover and the intermediate gear lined up to the notch on the plate it corresponds to.
 
I have done that. That seems to be my issue. When the cam is in the notch (dot lined up to the valve cover plate), the crank gear is aligned to the mark on the block, then the crank pulley is at 10 degrees. If I rotate the crank pulley clockwise to 0 degrees on the timing plate, then the cam is off 1 tooth as well a the crank. Yes, the are all aligned correctly and then that leaves the pulley mark at 10 degrees any movement towards 0 moves the cam and the crank. It just seems to be weird, maybe the pulley is supposed to be at 10 degrees when all is aligned correctly. I'll see if I can snap a good photo to upload
 
1.jpg2.jpg5.jpg4.jpg3.jpg6.jpg

first pic is of the camshaft gear, you can see the white aligned with the notch. second pic is the crank pulley timing mark is at the 10 degree mark, fifth pic is the crank gear, if you look close you can see next to the belt, the mark on the block, this is aligned with the notch in the front ring just behind the crank pulley. fourth pic is the dist cap looking down #1 plug wire is closest to the thermostat, the third pic is the dist with cap off, rotor pointing to the #1 position on the dist cap. last pic is of the carb air adjust screw.
 
8.jpgthis is the #1 cam lobe, both pointing away from each other valves closed. give me a few and I will take a couple more of how the belt is installed.
 
Pretty sure I got the tensioner locked down, everything stays lined up, however, it goes back to my first question. after aligning all the timing marks for the cam, crank and intermediate, I then installed the belt with the corresponding marks 1 to the cam 1 to the intermediate and two to the crank (starting with the crank). I then tightened the tensioner and rotated it by hand using a 24 mm socket and clockwise rotated the belt until tight, then I loosened the tensioner and tightened it again and did the same, still aligned. problem is once I put that damn pulley on it is at 10 degrees even with everything else lined up. see the photos, this is how it sits now. uploading the photos.
 
13.jpg14.jpg10.jpg11.jpg12.jpgfirst photo is the crank gear, second is the cam gear, belt set up, fourth intermediate gear, fifth is crank gear w/notch plate.
 
when the alignment is like this and the the damper pulley is attached and locked in place, and the timng cover on, it is at 10 degrees,
 
Seems that if I follow the above, that the crank gear will no longer be aligned to the timing mark on the block or does that matter?
 
I broke mine yesterday trying to get the crank pulley off, so I threw the old one which I replaced to get the marks so i could take the picture. I will be putting a new one on once I figure out my above problem with regards to the gear and the pulley. seems that the gear only goes on one way and the pulley as well so I am not sure how it is 10 degrees before. I bought a new pulley yesterday and it lined up the same. My thougts are that if I get all the marks lined up, then when installing the belt rotated the damper pulley to zero then tighten the tensioner, I may be able to get both at zero. from what I read, that last pic should have the piston at TDC, but when the pully goes on it indicates 10?
 
Thats exactly what I have as well, they lined up perfect and all marks on gears as well. I will try again tomorrow with resetting the timing with a new belt. and moving the pulley to zero degrees then install the belt.
 
Thanks for all the help, I appreciate everyone's input. This has been a pain over the last 2 yrs. It started when I took seawater into the fuel system, complete rebuild of everthing connected to the fuel tank. I can get it to start at times but never smooth or without some issue, I will not take it out until I am sure it is good to go. Can't say I put a lot of money into it, mostly time. but nonetheless, I am missed out on two seasons of great fishing.

Now with the carb, it is a remanufactured carb from flyingfishcarburetors.com. The accelerator pump is good. with the air adjustment are you saying to turn it out from seated further? meaning the further out it goes the leaner it gets?
 
I wil be tackling this today after work, it is now 11am so about 330 my time I will be in it. reinstalling the belt, etc. then we will see. I am really hoping that this information will fix it. I've said it before, I think I am close, just not sure if I am close to giving up or close to getting on the water. thanks again. Dennis
 
Thanks again. I am going to get the new belt tonight, but unfortunately won't get to the boat until tomorrow afternoon. The wife is working the
"Wicked" show that is in town and had the honey do list today after work. So tomorrow I will be hitting it until it runs smooth.
 
Got a new belt today. I first rotated the cam to tdc, then the intermdiate, then I put the crank to its respective mark. Same as above. I also had the dist removed. After installing the belt, I slowly rotated the engine so the belt would tighten up but not slip. After two revolutions around, I loosened the tensioner and the retightened the nut. Once this was done, I then rotated the engine again and all the marks were still aligned. I then rotated it slightly and slowly until the pulley mark was at 0 degrees, this (otherwise it still lined up under the 10 degree mark). The cam pulley dot is now one tooth clockwise as is the intermediate and crank, but the pulley is at 0 degrees. Then I put the dist in and aligned the rotor to the #1 plug on the cap.I then removed the throttle cable and adjusted the screw to two turns from when it hits the throttle plate, then tighetend the air screw to lightly seat. I then turned it out two full turns and started the enigne, it fired up and ran a bit rough, so I rotated the dist until it smoothed out, then after a few seconds there, it died. I turned the air screw out two more full turns (4 total). restarted and it ran and stayed running, although I still tries to die when throttle is applied (had to pump it slowly a bit to keep from stalling). But it seems to be better than before, didn't get the chance to put the light on it as it was getting hot, so tomorrow I will add the water housing back on and adjust the air screw out some more and see it it makes a diff. Still a bit confused as to why the gears all get aligned and then i rotate it 1 tooth clockwise and bang, she is running good.? Anyway...until tomorrow. I will also upload photos of the begining (with the new belt alignment, etc.
 
Looking at the picture of the crankshaft sprocket, the groove between two teeth should be aligned with the mark in the block, but it is not. Try aligning it between the red marks in the picture, then see what happens.

13.jpgTimingMarks6.jpg
 
Bad angle with the cell. it actually is lined up as you show, I will take another with a camera straight on. This is my entire issue. I can align these perfect all day, but once I add the crank pulley the mark on the pulley lines up directly under 10 degrees, it seems as if the crank needs to be rotated clockwise just a bit to get the pulley to 0 degrees. Should I be looking at something else that could be the cause of why the pulley will not hit 0 once attached to the crank sprocket? I had placed a new pulley straight out of the box and it did the same. I wonder if there is a difference in the pulleys between the auto and the marine with regards to placement of the timing mark? I do know that on the volvo forum turbo tricks, that one person had said that the timing for the engine should be at 12 degrees btdc and the volvo penta states 6 degrees. We have a volvo penta office locally, and a call was placed by a friend of mine who was in the navy with the special boat teams and they used the old vovlo pentas. So he called the VP, looking to get one of their techs to help. We will see, meanwhile, I will continue to play. Another thing...could I just line it up correctly, then when I put the pulley on, make a new mark at 0 in the pulley and use that for the ignition timing?
 
Maybe I am missing something here, but wether you line-up the mark in the crankshaft sprocket with the mark in the block or you line up the mark in the vibration damper with the zero in the timing gear cover, you should have #1 piston on TDC in either case. Since both vibration dampers are identical, re-marking them would not be a solution. I don't know how you are installing the belt, but you may want to re-check the installation process. I would try installing the timing belt and verifying that the marks between block and the 3 gears are lined-up (that is, they haven't moved), then without moving anything try installing the timing cover and see if the mark in the pulley lines-up with the zero in the timing cover.
 
Never does, it always hits at 10 degrees. That is my issue. I just finished this again for the at least the 25th time. spot on with all three mark. Brand new belt, has arrows and two lines, they all are right where they should be. Then once I install the timing cover and place the pulley on, the timing mark is at 10 degrees. I tried moving the pulley to zero degrees and then installing the belt, same result, all dots line up except the crank gear (in this case) because I moved it to the zero mark on the timing plate. If I just do the gears, then the pulley is at 10 degrees. I'm stumped. one guy said to line everything up, intall the belt, the turn the crank to zero and stab the distributor? I tried that too, but doing that moves all timing dots one tooth forward.
 
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