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Made in Canada. Bought for Harmonic Balancer double pulley for L-79 with p/s. Joe can you tell me want applications this pulley will work for? I am having trouble installing, lip on pulley seems to large and will not easily enter harmonic balancer. I know I must be doing something wrong. I believe the pulley mounts and then the harmonic balancer bolt is then installed. I also have an add on pulley for the p/s GM# 3751232 also made in Canada. Is that correct?
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Re: GM# 3744043-BA Harmonic Balancer Pulley
Eddie----
GM #3744043 is a balancer pulley for many 63-68 Corvette applications. I need to know your specific year model.
The GM #3751232 is an "add-on" pulley used for SOME applications with power steering.In Appreciation of John Hinckley -
Re: GM# 3744043-BA Harmonic Balancer Pulley
Joe, the car is a 66 L-79.Comment
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Re: GM# 3744043-BA Harmonic Balancer Pulley
Eddie -
The pulley configuration for your '66 L79 w/N40 would be a 3858533 crank, 3770245 W/P, and a 3834720 cast iron P/S pulley. An application for the '043 pulley is under this link,
Mark #35760Comment
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Re: GM# 3744043-BA Harmonic Balancer Pulley
Mark, do you know if the crank pulley has a lip that fits into the harmornic
balancer. Am I right to install the pulley's and then the balancer bolt passes
through the pulleys and into the threaded crank? Non corvette people I have
ask say the bolt goes in and then the pulleys. I don't see how that will work
with the bolt and pulleys I have.Comment
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Re: GM# 3744043-BA Harmonic Balancer Pulley
Eddie-----
I agree with Mark's information.
The pulley does have a lip on the rear of the center hole and that lip DOES fit into the hole on the balancer. Virtually all balancer pullies have this lip EXCEPT the "add-on" pullies like the 3751232.
The balancer bolt and large washer are installed AFTER all of the crank pullies are installed. In your case, there is just one crank pulley which is the GM #3858533.
There is some "mis-information" out there regarding pullies for your application. The genesis of some of this information is GM. For instance, the 1966 AIM shows that the GM #3751232 is THE crank pulley used for the 1966 with L-79 and N-40 application. For one thing, the 3751232 is an "add-on" pulley of 1 groove. It CANNOT be used as a stand-alone pulley for any application. For another thing, the 3751232 was not even used as an "add-on" pulley for your application.
There is also incorrect P&A Catalog information regarding pullies for your application.In Appreciation of John HinckleyComment
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Re: GM# 3744043-BA Harmonic Balancer Pulley
Thanks for the info Mark and Joe. Since I didn't have a source for the 3 groove pulley when I started the engine build up, I opted for what I was told was a functional equivalent. I am worried now that the lip does not fit with ease. Should the pulley install with ease or is the fit such that the balancer bolt whould have to pull the pulley up to the harmonic balancer.Comment
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Re: GM# 3744043-BA Harmonic Balancer Pulley
Eddie-----
First of all, you don't require a 3 groove pulley or the equivalent thereof. The 2 groove pulley is all you need. The inner groove drive the waterpump pulley and alternator pulley. The outer groove drive the waterpump pulley and p/s pump pulley. That's all you need.
Usually, the lip on the rear of the pulley center hole fits quite tightly into the balancer snout hole. This is necessary to ensure that the pulley is exactly centered on the balancer. However, if there are any burrs or impactive damage on the area of the balancer hub surrounding the balancer center hole (such as the kind of damage that occurs when someone POUNDS a balancer on), the center hole will be too distorted for the pulley ridge to fit into. In that case, you'll need to use a grinder to "dress" the balancer center hole.In Appreciation of John HinckleyComment
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Re: GM# 3744043-BA Harmonic Balancer Pulley
Hi Eddie:
Just to reinforce what Mark Gorney and Joe Lucia have said, the 3744043 pulley is not the correct crank pulley for your car. Your crank pulley should be a 3858533 dual, deep-groove pulley. The outer groove is used for the power steering pump, so no third groove is needed.
Either way, the lip should fit snugly, with only hand pressure, into the balancer. The crank bolt and washer go in last, on top of the pulley.
It is not a good idea to mix and match pulleys that were not part of the complete set as engineered by GM. In addition to the obvious differences in diameter that can affect the rotational speeds of the driven elements, the center-to-center distances of the grooves in the deep groove pulleys are larger than the center-to-center distances in the standard pulleys. If you mix and match standard and deep-groove pulleys you will end up with alignment problems.
The most straightforward path is to obtain the three pulleys that Mark listed in his posting, since these are the correct ones for your car. I think that at least one of the three is still available from gmpartsdirect.com, and the others should be available from a variety of sources of used and NOS parts.Comment
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Re: GM# 3744043-BA Harmonic Balancer Pulley
Thanks for the help. The reason I am confused about the pulleys is.
Page 85 of the NCRS technical Manual states 2 belts, 2 groove pulley on crank
2 groove pulley on water pump for 327 w/power steering.
Page 86 Under Crankshaft Pulley for Base engine uses 2 groove pulley. Power Steering cars have an additional one groove pulley inserted within the crankshaft pulley to make a total of three belt gooves.
Page 86 under Crankshaft Pulley for L79 350hp manual states two grooves. Power steering cars use a triple groove pulley. (My Car)
So this is why I thought I had to have triple grooves on the crank.
Anyway I will try to locate the pulleys you guys have recommended.Comment
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Re: GM# 3744043-BA Harmonic Balancer Pulley
Eddie –
I was interrupted and was unable to respond to your questions. The 3744043 pulley, shown in the A.I.M, is used on the ’65 Corvette base engine. As for ’66 L79’s, Joe L. & Joe R. have it correct, the ’66 A.I.M. has a misleading illustration of the L79 pulley setup. My car is an early 300hp with C60 and K19 (smog); while finding the smog parts I managed to collect the ’66 & ‘67 SB engine pulleys to try to understand the puzzle.
The L79’s are more complicated depending on the driven options. Some details are; the 3751232 P/S add-on pulley does not fit into the 3858533 deep groove pulley. It fits, orientated one way, into the standard 3755820 one groove and two groove 3850838 crank pulleys. L79’s with A/C use the base 300hp pulley configurations for the crank, water pump, and P/S. The thickness of the SB harmonic balancers dictate the pulleys and spacers for correct alignment. I can send a chart listing the SB pulley sets and pictures of L79 engine pulleys.
Mark #35760Comment
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Re: GM# 3744043-BA Harmonic Balancer Pulley
Mark,
I sent you an e-mail requesting all the info you have including pictures.
Regards,
EddieComment
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Re: GM# 3744043-BA Harmonic Balancer Pulley
Hi Mark:
Your description confirms what my own research was starting to point to. I have a 67 300 HP with power steering and A/C. After the engine tossed a belt at high RPM, I decided to convert to the L79 deep groove pulley set.
What I have concluded is that you can't use the deep groove pulley set on an A/C car with power steering. The problem is that the center-to-center groove spacing of the deep groove pulleys is larger, by about 0.1 inches. For the deep groove pulleys to line up properly on an A/C car, there would have to be a special version of the A/C clutch pulley, a special version (in addition to the two that already exist) of the power steering pump pulley, AND a special version of the add-on 3751232 crank pulley used for power steering.
It looks to me that GM just threw up their hands and decided it wasn't worth the extra cost to develop a special pulley set for this configuration. I think the only pulley that was changed for this configuration was the alternator pulley, making it the only deep groove pulley used on L79 cars with A/C and power steering.
Does the above sound correct to you? One thing I'm curious about is whether GM used the deep groove pulley set on cars with A/C but no power steering. In this case everything would line up exept for a possible small offset on the A/C compressor pulley alignment. From your description it sounds like they used the base configuration pulley set for ALL A/C cars, regardless of whether the car had power steering.Comment
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