aq171

Ferenc Gemesi

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Feb 2, 2020
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4
Hello!

I like to know what the difference Volvo Penta AQ171A and AQ171C?

Thank you for you answer!!
Frank
 

Scott Danforth

Grumpy Vintage Moderator still playing with boats
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2 years. The A is first year of production, B the second, C the third
 

Ferenc Gemesi

Recruit
Joined
Feb 2, 2020
Messages
4
Hello Scott!
Maybe you help me.
I change engine in my boat.
AQ170(6cyl) to AQ171(4cyl).
Have a small? problem for aq171.
Toothed belt not exactly. It is not in the middle.
What can be the difference, what could be wrong, or good anyway?

Very thanks for all answer.

Frank Click image for larger version  Name:	IMG_3741.jpg Views:	1 Size:	155.1 KB ID:	10894281
 

QBhoy

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Hesitant to tell you, but generally these can be thought of as problematic in a boat. Known for cam belt issues if not kept an eye on, as well as cylinder head issues. A number of U.K. made boats were optioned with these engines in them. Didn’t go well over the years compared to the alternative GM engine options. Significant difference in value between them as a result, these days. I’m not sure I know of one of these in a boat that hasn’t been rebuilt or replaced at least once, by now.
 

jerryjerry05

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This post was started in February last year.
Then reopened by someone in June?
 

bruceb58

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The way the tensioner works is you loosen the bolt on the tensioner, allow it to tension the belt and then you tighten back up. If you don't the tensioner pulley will be loose and not be in alignment causing your belt to move like it is.
 

QBhoy

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The way the tensioner works is you loosen the bolt on the tensioner, allow it to tension the belt and then you tighten back up. If you don't the tensioner pulley will be loose and not be in alignment causing your belt to move like it is.
Just need to watch it doesn’t slip. Being a timing belt an all.
 

bruceb58

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Just need to watch it doesn’t slip. Being a timing belt an all.
I have done many of these on the same engine in the Volvo auto. It's probably the easiest timing belt I have ever come across. There are alignment markers on all the pulleys and typically on the belt too. Pretty hard to screw up.
 

QBhoy

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I have done many of these on the same engine in the Volvo auto. It's probably the easiest timing belt I have ever come across. There are alignment markers on all the pulleys and typically on the belt too. Pretty hard to screw up.
You’ll be right for sure Bruce. No bother to a guy like you. Perhaps more scary to an amateur
 

bruceb58

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You’ll be right for sure Bruce. No bother to a guy like you. Perhaps more scary to an amateur
I was an amuteur the first time I replaced one of these. Fortunately, the B21 is a non interference engine so pretty hard to eff it up and damage anything.
 

kenny nunez

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Volvo and maybe some aftermarket suppliers provide yellow stripes on the belt to help Aline the timing marks on the respective sprockets. There is a small hole on the tensioning rod you put a small rod through that keeps the spring compressed on the tension pulley bracket to make it easy to install the belt. Then remove the rod to tension the belt. I always spin the engine by hand until the belt marks come back around and land where they started from. Sometimes the belt does not line up with marks on the sprockets and you have to start over. The engine might start if the belt is off by 1 tooth so you have to check to be sure timing marks on the belt and sprockets line up again. It takes about 25 reveloutions.
 

bruceb58

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All you have to do is make sure the engine is at TDC and the camshaft is aligned correctly. The shaft that rotates the distributor can be compensated for by rotating the distributor when you time the engine.
 
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