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Intake manifold question

M

my_heap

Contributing Member
I have a AQ 120-B engine.
It

I have a AQ 120-B engine.
It has water coming up through the carberator.
No sign of water in oil. Could this be caused by a bad intake manifold gasket?
Can I take off intake manifold and tell easy by looking at gasket? Or if I do a compression check can I tell if the gasket is bad that way assuming the head gasket is ok.
Thanks for any advice
 
By any chance did your motor d

By any chance did your motor diesel and then suck in the water. When my motor would diesel when it would stop the motor would actual turn the opsite direction.
 
"Well, it seams the head gaske

"Well, it seams the head gasket must have started leaking causing engine to suck water in cylinders. I had no idea of that when engine stalled. I tried to start it and it locked up causing probably timming belt to break.
So now engine has no compression.
I will junk engine. Thanks for the help."
 
"Get the water out, change the

"Get the water out, change the belt, and You most probably has a working engine again! The reason You have no compression is the camshaft is not turning and some valves are stuck open!"
 
Thanks Mort. I am not a great

Thanks Mort. I am not a great mechanic but I have nothing to lose here. How big of a job will this be?
I had a mechanic come out to look at it. After he saw no compression he told me have to tear engine down to better know what wrong. I was not really wanting to put more money into this motor if it is not worth fixing. He charge 40 dollars per hour. What kind of money or how many hours to replace belt. I not even sure broke. I do know no compression and the water comming in carb.

I have had motor up to 200-220 degrees but it immediately cooled back down. When water came in carb it was running 180-190 degrees.

I really want to fix this problem
 
"Timing belt, probably timing

"Timing belt, probably timing belt gear on cranckshaft (corroded and reason for failure).
Time to replace might depend on the engine room and accessability to the front, but roughly 1-2 hrs. Cheapest mech might be an 'old' volvo car mech, the engine and parts are the same as the Volvo B21/23 (140/240 series), except You might need to replace some of the 'square' o-rings that Penta uses on the water tubes!.
Take down the heat exchanger unit and the front covers to get access. Compress the roller tensioner and lock it compressed, line up the gears (new on the cranck shaft), on with the belt (it is clearly marked), release the tensioner (check the bearing and replace if bad).
The biggest job might be to get the water out of carbs and engine. Total parts cost should be less than 100$, but honestly not quite sure of US prices, but if El Pescador is still lurking around, he might be able to give them!
However a manual is always good to have around!"
 
"Just noticed your post morten

"Just noticed your post morten ,and your explanation on the adjustment for the roller tension.have just replaced my head and manifold on my AQ145A and when i put my belt back on and released the tensioner i noticed that the spring just went to a given position when i pulled out the pin that i had in place to hold the spring back.is there any further adj to be done after i tighten the bolt that holds the tensioner to the head.i ran the motor and there seems to be a bit of slack on the belt when i accellerate the engine.is this normal."
 
"I have in my time noticed som

"I have in my time noticed some variation in aftermarket belts and always used the original ones. Another thing which is essential is that the crank shaft gear should be changed and not just 'cleaned' from corrosion as this will reduce its original diameter and give less tension, and the same goes for a worn tension bearing. But anyway You might see a slight slack under certain conditions, like accelerating even with everything new and original. The same You may notice on a normal alternator belt even if properly tightened and load is put on the alternator."
 
"Happy new year Morten and res

"Happy new year Morten and rest of the forum participants. Yes I am still lurking around but I am too busy during the week to participate.

Cameron, I have already responded to your question in another thread about obtaining an AQ120. If your current engine is NG, I think your best option is to buy a suitable automotive block and marinize it. If you decide to go that way, I can guide you through the process. However, I also think that Morten is right when he suggests that you change the belt and timing gears, and I advise you to explore that option; it does not make sense to me that none of the cylinders have any compression unless the crankshaft has split by number 1 crank throw or the timing belt has slipped (or a totally ruined head gasket, which is highly unlikely). You can buy a set of used timing gears from a car wrecker and a new timing belt from your friendly neighbourhood autoparts store for a total of around $150; and if you want to do the job yourself, you should also buy either the Seloc or Clymer manual, which will guide you to the process. In fact, you should buy one of these two manuals (or both) if you own a pleasure boat with a Volvo engine and outdrive.

Stan, are you still fighting with your engine? Boy, that’s taking a long time. Anyway, I assume that you did not change the belt tensioner, which tells me that the slackness you are experiencing could be due to the spring being weak or sticking in the same spot after years of not moving. No, there is no further adjustment to be done, as the spring in the belt tensioner should compensate for any stretching that the belt may experience. However, as Morten very well said, you can always see a bit of slackness at higher RPM on the timing belt, especially while accelerating."
 
"El Pescador.no not fighting w

"El Pescador.no not fighting with the engine.all the job has been done.got the head welded on number 4.replaced exh manifold,the whole job is done.running nice.just noticed that there was a bit of slackness on the belt on acceleration and i would say that from your comments that this is normal.i did take the tenstioner of and clean and adjust bearings seems ok with no dramatic play.the spring is doing its job,but when this was taken of by the haed manufacturers i was a bit confused how to put it back.where the nut that secures the big washere onto the head there seems to be a bush missing but after working this out it seems to me that is the free spave for the tentioner to move to its home position??.the other problem i had was that the timing was out,so i allined the timing marks on the cam gear and bottom crank gear and moved took the distributor out and re positioned this to fire on number 1 and every thing is fine ,starts good.have to do river trial this afternoon.will let you know.the olny thing im not sure of it when i set the timing with a timing light and rev the motor the timing light indicats the timing mark on the crank pully advances to say 30 deg.and when i rev the motor quick the response on the accellation does not seem to be as responsive as before i done the head.any suggestions will be appreciated."
 
"Stan, here is one check you c

"Stan, here is one check you can do to ensure that the belt is not too slack: grab the timing belt with two fingers on the distributor side and try to twist it from starboard to port. You should be able to rotate it about 90º: if you can turn it more, then it is too slack. To correct this, just loosen the tensioner nut and the spring will set it at the right tension; then, tighten the nut again. By the way, all this is clearly explained in the Seloc and Clymer manuals, you will save yourself a lot of grief if you make a modest investment and purchase either of them (or both). Believe me, it will be money well spent.
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The ignition timing setting for your engine is 4º BTDC at idle (900 RPM) and 30º at 4000 RPM with a point dwell of 62º+3 (this information is also in the manuals). If you don't find the acceleration as responsive as before, you may want to verify that the belt was installed correctly (that is, it has not jumped one tooth or more) and that your carbs settings are correct. Also (again, my favourite ignition subject
biggrin.gif
) you can consider installing a Pertronix electronic ignition kit to improve performance.

Good luck in your river trial."
 
Well had the boat out for rive

Well had the boat out for river trial and it performed like new boat.plent of power .WOT 5200rpm(had a little left but did not want to push it)reached on my speedo 34 MPH.I thought theses motors had a max rev of 4800.do i keep it at 4800 and not exceed .is this a safe level.Havent chech the belt slacknes test yet but will do that on next.
 
"Your engine RPM are too high,

"Your engine RPM are too high, try a propeller with two more inches pitch."
 
I have a 15 X 17 prop on now.a

I have a 15 X 17 prop on now.are you saying i should have a 15 X 19 ? What would be the result in this will i get more top speed?
 
"My apologies. Your engine&#39

"My apologies. Your engine's maximum operating speed is 5500 RPM (not 4800), so you have the right propeller installed."
 
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