Thread: Harmonic balancer on 454 has 4 timing marks.....

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Found several pics I took of the motor before the install. I was able to zoom in and cut the pictures to show the balancer marks. After finding the pics, it's obvious the "other three lines" arent factory to the balancer. From my prospective with the motor installed in the boat. The lines looked straight and factory. The attached pic, shows a different story(pic 1).

Since I know the installer set TDC to the long line and the motor seems to not be 180 out, I guess I need to put a timing light on it(or set to ear, considering Pat's comments).

I also realize I need to find a way to make sure TDC is TDC. I'll figure something out.

Also looking at internet pics of other factory balancers(which this one appears to be). I noticed the long timing mark appears to match most other pictures found. The mark is in the same spot, relative to the four holes in the side of balancer(pic 2). So likely timing marks not slipping, due to bad balancer.

So seems the motor is to far out of time or the 850 is just to big.

Though on initial startup the cam was big enough to draw water back into the motor. I had to change exhaust to "thur hall". The cam overlap sucked water back into motor, because factory exhaust was routed into the water, though outdrive. New exhaust exits rear of boat into air and corrected that problem. So with such a cam and considering boats typically run higher RPM's. The carb such be right on.

Guess maybe a leak at the base of carb should be considered also.

Know more tomorrow evening, as I will be messing with it. Thanks again guys. I know this isnt really a boat forum. I appreciate the advise anyways!

Originally Posted by repoman3809

Found several pics I took of the motor before the install. I was able to zoom in and cut the pictures to show the balancer marks. After finding the pics, it's obvious the "other three lines" arent factory to the balancer. From my prospective with the motor installed in the boat. The lines looked straight and factory. The attached pic, shows a different story(pic 1).

Since I know the installer set TDC to the long line and the motor seems to not be 180 out, I guess I need to put a timing light on it(or set to ear, considering Pat's comments).

I also realize I need to find a way to make sure TDC is TDC. I'll figure something out.

Also looking at internet pics of other factory balancers(which this one appears to be). I noticed the long timing mark appears to match most other pictures found. The mark is in the same spot, relative to the four holes in the side of balancer(pic 2). So likely timing marks not slipping, due to bad balancer.

So seems the motor is to far out of time or the 850 is just to big.

Though on initial startup the cam was big enough to draw water back into the motor. I had to change exhaust to "thur hall". The cam overlap sucked water back into motor, because factory exhaust was routed into the water, though outdrive. New exhaust exits rear of boat into air and corrected that problem. So with such a cam and considering boats typically run higher RPM's. The carb such be right on.

Guess maybe a leak at the base of carb should be considered also.

Know more tomorrow evening, as I will be messing with it. Thanks again guys. I know this isnt really a boat forum. I appreciate the advise anyways!

yep i know all about the EX running threw the prop . many time s the flap valves would come apart .many times you would see parts of them when you did a stren drive R&R look like the heel of a shoe... we did not see it ....more to the point did not want that job on some boats and was a winter job. it was not fun .but did not rate as hi on the list as a gimbal housing that bolt threw the transom i did drink abit back then. some of the work really did suck . that job was not much fun

Well here's the update, and not good. Fiddled with the motor all day. Made sure was TDC on compression stroke, made sure button was on one. Made sure all wires followed the proper firing order. It was all good. Also new gaskets for carb(yes gasket(s), it's got an adapter plate).

Motor still only started by matting the throttle(or pumping 20 times). I advanced the timing by ear, till motor sounded best. At this point motor started a lot easier. Typically one or two pumps on throttle(sometimes none). While it started easier and with less fuel, it definitely was fighting itself. The motor would crank slower and almost stop, right before it started(i assume combustion was premature pushing piston back down). But it was starting.

I had to put a timing light on at this point. Turns out I was way off timing tab and I'd guess roughly 32-34 degrees BTDC at idle. Tried moving back to end of timing tab(16 degrees). Motor idle would drop off and motor would stall or be on verge of. The start up was back to matting throttle or pumping twenty times, at 16 degrees BTDC.

Checked fuel pressure again(just after fuel pump). Pressure still 5-1/2 psi. Advanced timing and restarted, checked vacuum. Read about 13 inches and was pretty steady(maybe inch either way periodically). This reading was with the ridiculous base timing(32-34BTDC). Obviously as I retarded advance RPM and vacuum dropped. Best I could get was crappy rough idle around 900, with 8 inches of vacuum. Vacuum reading was consistent with lumpy idle(if idle when up, so did vacuum. if idle when down so did vacuum).

Finally smartened up and got out the compression tester. Tested 2-4-6: roughly 110psi to 120psi(low but enough. But for big cam too low, right?). Regardless, #8 was around 65psi(checked it 3 times, along with gauge/S.P. hole connection). NOT GOOD!

At this point I was tired, sweaty and ticked. I packed up and went home. Leaving the rest of the cylinders untested and didn't bother shooting a little oil down #8.

Worst part I've had the motor for some time. I doubt the shop I bought it from will give me a break(gonna try though). Should have done a test right there in the shop.

Lesson learned, regardless of outcome! To anyone as dumb as me(hope none). Do a compression test before you buy. It doesn't matter who your buying from either(I bought from reputable marine shop). Put a starter on it, jumper cables, jumper wire and good battery. Or just test it by hand. Just find a way to do it. Don't be a dummy like me!