Re: No power under load? Engine, starts, idles and revs p...

zinc2u · Post by **zinc2u** » Mon Apr 04, 2016 2:09 pm

It sounds like your engine is working but not delivering the full horsepower. For the engine to develop full horsepower under load, it is going to need;
a) air
b) fuel
c) compression
d) ignition
For AIR, you pulled out the air filter. That gives the engine plenty of air.
For FUEL, you tried looking in the carb from the air cleaner and noticed fuel coming back at you. That is not correct. You could have a problem with the float setting, the needle & seat, or jetting system.
For COMPRESSION, you need to measure the compression on each cylinder. For the 600 cars, you should have around 160 psi. With your problem, you need to know if you have good compression.
For IGNITION, you need to know if the spark plugs are working under load. With no load, it doesn't take very much voltage to spark the plugs. At high load, it requires more voltage to spark the plugs. If you have a defect in the spark plug wires, spark plugs, or ignition coil, the voltage necessary to create an arc will not occur and the cylinder will not fire.
Regarding timing, it is nice to know the timing at idle but your problems are occurring at a higher rpm. You need to know if your vacuum and mechanical advance are working properly. Check the sedan shop manual for the advance curve and you can see the curve for degrees of advance vs engine rpm. The 2 problems I have seen with the mechanical advance are the two springs become weak allowing the advance to go to maximum at too low of an rpm and the advance mechanism gets covered in grime so the weights do not allow the advance plate to rotate. The vacuum advance you can check by putting some suction on the hose (the one which goes from the advance to the base of the carb) and listening for the engine rpm to increase.
I think your intake manifold seal is ok since you say it idles ok and travels under light load ok.
I think you do have an issue with your carb but it is not the main issue. Restricted fuel flow could cause your problem but you appear to have excess fuel. Why is the fuel coming back toward the air cleaner when the engine is try to suck air in the opposite direction? Is there an obstruction in the carb?
good luck,
Dale

> Flat land, slight incline the car moves and can build up speed shifting all > the way to 4th gear.
> Uphill or with a passenger it loses
> power?
> Engine starts, idles and revs fine. But once I hit the streets > it struggles under load. (hill or with passenger/s) > Any > suggestions?
> Thanks in advance
> 71 sedan

zinc2u · Post by **zinc2u** » Tue Apr 05, 2016 5:34 pm

Good to hear you worked out your problem. I believe that you moved it one tooth and saw a difference but I've never seen a one tooth movement make that much of a difference. But I can see where it would happen if you are at the extreme edge of a properly centered camshaft. I suggest you check your camshaft position again and this time verify your timing marks are correct. For the pulley, the "T" should occur when the piston is at top dead center(TDC). For the camshaft, the scribe on the cam sprocket should correspond with the cam lobes being at their lowest spot.
To determine if the piston is at TDC, remove a spark plug (either side) and put something long and narrow in it (e.g. wooden dowel, screwdriver, soda straw) and use it to determine TDC by watching it move up and down.
Also, how easy was it to move the cam chain one tooth?
Did you have to loosen the chain tensioner? Did you have to remove the left/right cam holders to drop the camshaft? If not, you may have a stretched cam chain and it jumped one or more teeth which caused your problem. Or you may have a cam chain tensioner which is not functioning properly.
Things to consider so the problem does not reappear.
Dale
In a message dated 4/5/2016 3:03:40 P.M. Pacific Daylight Time, anzhonda600owners@yahoogroups.com writes:

> Well after a couple weeks messing with
> this,I rolled the timing chain 1 tooth....runs like a bat outta,well you > know
> On Monday, April 4, 2016 12:35 AM,
> "'Bill' billmyong@... [anzhonda600owners]"
> wrote:
> [
> Attachment(s)
> from Bill included below]
> Also, don't leave out
> the jets, these are the three jets located in the center of the later > carb. I use a set of dental root canal hand drills to open the > holes. The dental tools are really great because they are strong and > will clean the gum and crud really well.
> Bill
> From:
> anzhonda600owners@yahoogroups.com
> [mailto:anzhonda600owners@yahoogroups.com]
> Sent:
> Sunday,
> April 03, 2016 10:30 PM
> To:
> anzhonda600owners@yahoogroups.com
> Subject:
> RE:
> [anzhonda600owners] No power under load? Engine, starts, idles and revs > perfectly
> I had a similar
> problem with the engine running great, flying down the freeway at 65 and it > felt heavy, I replaced the center silencer and muffler now it screams, but > because the center pipe is replaced with a straight line muffler it is a bit > loud, but okay.
> And its much better pickup and nice
> power at top end.
> I would check them out.
> Bill
> From:
> anzhonda600owners@yahoogroups.com
> [mailto:anzhonda600owners@yahoogroups.com]
> Sent:
> Sunday,
> April 03, 2016 9:53 PM
> To:
> anzhonda600owners@yahoogroups.com
> Subject:
> Re:
> [anzhonda600owners] No power under load? Engine, starts, idles and revs > perfectly
> A tooth or 2 off could make total sense though. Follow Bills > instructions for checking timing via the manual and it would solve all your > issues > ------------------------------------------
> Eric Geiger
> PRG-Nocturne
> XXX-XXX-XXXX
> Egeiger@...
> On Apr 4, 2016, at 12:50 AM, Eric Geiger
> egeiger@...
> [anzhonda600owners] anzhonda600owners@yahoogroups.com
> wrote:
> > Sounds like timing to me. But I'm no expert
> > ------------------------------------------
> > Eric Geiger
> > PRG-Nocturne
> > XXX-XXX-XXXX
> > Egeiger@...
> > On Apr 4, 2016, at 12:48 AM,
> > promoter213@...
> > [anzhonda600owners] > anzhonda600owners@yahoogroups.com
> > wrote:
> > > Rubbers looks good. But I should check the hoses. Thanks Bryan.
> > > I had thoughts that maybe the filter cabin was clogged so I removed > > > it to have a better look, no obstruction. While the filter cabin was off I > > > decided to rev the engine with no filter and placed a mirror so I > > > can see the inside of the carburetor and check if the piston is moving and > > > picking up fuel.
> > > To my surprise fuel was being spit out towards the air cabin as I > > > pressed on the accelerator. My tiny mirror got wet.
> > > I'm going to check on the timing tomorrow and update.
> > > Sent from my iPhone
> > > On Apr 3, 2016, at 8:03 PM, "Bryan O'Shaughnessy
> > > bryanoshaughnessy@...
> > > [anzhonda600owners]" > > anzhonda600owners@yahoogroups.com
> > > wrote:
> > > > Look at the
> > > > boot that connects the carburetor to the cylinder head to see if it is > > > > leaking air in. Check the fittings at the ends and also look for > > > > cracks in the rubber; it is probably forty years old so don't be > > > > surprised if the rubber is cracked. If not look for other broken > > > > vacuum hoses that draw off the carburetor. Also check your air > > > > cleaner and the air-route into the carburetor. Over time, it may > > > > have become clogged. --Bryan O
> > > > > From:
> > > > > "
> > > > > promoter213@...
> > > > > [anzhonda600owners]" > > > > anzhonda600owners@yahoogroups.com
> > > > > To:
> > > > > anzhonda600owners@yahoogroups.com
> > > > > Sent:
> > > > > Sunday, April 3, 2016 2:07 PM
> > > > > Subject:
> > > > > [anzhonda600owners] No
> > > > > power under load? Engine, starts, idles and revs perfectly
> > > > > Flat land,
> > > > > slight incline the car moves and can build up speed shifting all the > > > > > way to 4th gear.
> > > > > Uphill or with a
> > > > > passenger it loses power?
> > > > > Engine starts,
> > > > > idles and revs fine. But once I hit the streets it struggles under > > > > > load. (hill or with passenger/s) > > > > > Any > > > > > suggestions?
> > > > > Thanks in advance
> > > > > 71 sedan