The first part of this posting is from Grant's blog
Some More testing & Sorting Out Of Monty.....
Gidday,Well after the last few weekends of "testing out" and travelling solo in the chev and venturing a little further each time, I arranged with Ray to come up and come out for a few breezy drives on this crisp winters morning but first on the cards was a lesson in "brake adjustment" as ole Monty had started to develope a bloody loud squeak in the rear wheel when you applied the brakes and only after they had warmed up and also the brake pedal inself was getting less and less so I gathered after 220miles the new brake bands had "bedded in" by now, so time to adjust them up, but does one do this?
With the brakes all adjusted up nicely and me now knowing what to and how to adjust the bands,we both jumped in the chev all rugged up and headed off down the hwy to Yarragon which is quickly becoming a favour little coffee haunt....
Now this is where Rays 30 plus years of vinatage Chev experience kicked in because as soon as we started to head out of town while traveling up a slight incline, ole Monty gave a few quick stumbles at 45mph, I had noticed this before over the past weeks at this speed but just thought nothing of it, "its old car habits" as this is the only vintage car I have very been in... We discussed it and listened a little more as we headed to Yarragon and to my knowledge it was starting to stumble more than it had on other occassions but today I was driving it a little quicker than normal.....
We downed our coffee's and headed back to the resto shed to sort it out, where we quickly had the rocker cover off, the spark plugs and leads out and the distributor cap off.. We adjusted the valves and timing, cleaned and set the points, cleaned the spark plugs and distributor cap etc and had it all going again in no time..
Off we went out the onto the Hwy again and Ole Monty pulled away up the slight rise very well this time and reached 45mph quickly and felt very smooth, no stumbles and it was smiles alround from us both..... But no, how wrong were we?, the stumbles started again and it began to lose power and drop back to 40mph, "It had to be the bloody fuel" Ray said, "its not elctrical, turn a round and head back home"....
Again in the driveway we headed and we slowly roll into the resto shed, Ray grabs for the service manual and reads up some specs to check some figures and I unscrew off the bottom of the carby bowl.... "Theres your problem, the float is adjusted wrong and sitting at the wrong level, it was slowly starving of fuel at top speed", the correct level was set, the bowl goes back on and out the gate we go again...... BEAUTIFUL and now oh so much power comes from within this 21hp engine, up Thorpy Hill we headed to the top and it did not miss a beat, although a little slow, it is a long hard climb and the engine did not stumble once.... We turned around at the summit which overlooks Trafalgar and I pointed the radiator cap for home and at one stage 55mph showed up on the speedo and on Rays GPS which we had stuck to the windscreen it read 85kph..... Bugger ME!!... Monty was flying!!.
This fuel starvation was not an issue or noticeable on startup, idle or while driving around town because naturally the revs are not high and the carby bowl/fuel flow could keep up with the useage, and even out on the roads tavelling at 40-45mph it was right on the limit with only the slightest of stumbles which I noticed and thought it might be the fuel vac tank reloading but thought it was nothing to worry about as the engine was running very smoothly, and it would cruise along fine 95% of the time and me being the novice I am, put the stumbles down to Monty being just an old vintage car with a few quirky habits, live and learn I guess, but now all is good and it is running better than it has in quite some time.....
Thanks Ray for spotting this problem and sorting it out today.......
From a Technical Perspective the following is Ray's slant on the days events, very enjoyable, and thanks again to Grant for lunch.
Today was meant to be a play day for Grant and I, a simple adjusting of the brakes, to be followed by a series of long test drives.
The day started off to plan, we adjusted the brakes on all 4 corners, and set off for a coffee run to Yarragon, which is about 8 k's from Trafalgar. Grant had previously told me that on occasions Monty had a "surge" or "stumble" at certain speeds on certain roads.
Well, there were no surprises, and as soon as we hit road speed of about 80 k's there was a definite surge and momentary loss of power. We suspected fuel, but with these old bangers you can never be sure. And in my case, being a strange car you don't know all the behaviour patterns.
But the good news at this stage was that Monty's brakes were working very well.
Anyway, while we had an enjoyable coffee and a nibble, Monty dumped a quantity of water that he no longer needed in the main street of Yarragon. I was amazed by the amount of attention Monty received, as the average person would look at the "very pre loved" paint and panels and not realize that beneath the skin Monty is as restored as any shiny 28 Chev on the road.
We made it back to the resto shed and started a series of checks and adjustments to eliminate this inconsistent surging and loss of power. A couple of simple adjustment made the situation seem worse, so I said to Grant the only way to fix this puppy was to go back to basics, do a complete tune and hopefully by process of elimination cure the problem.
So knowing Monty was in need of a tune up at least, it was a good excuse to do the lot, and we set about the following:
1. Checked, cleaned and reset the points from 18 to 23 thou.
2. Cleaned up the contact surfaces on the dizzy cap.
3. Removed excessive play from the advance and retard linkage, which was not moving the full measure when fully advanced.
4. Removed excessive play in the carby linkage.
5. Removed, cleaned and re-gapped the plugs at 30 thou
6. Reset the valve clearances which were all way over spec.
At this we took Monty for a test drive, and I was confident that what we had done would eliminate any suspicion of the problem being electrical. The result was worse, Monty ran like a dog, and even though he idled smoother and quieter, on the open road or hills, power would disappear on anything that looked like a hill or after a short run at high speed.
We tried several road side stops adjusting the air / fuel mixture, no luck, but what came to the surface was all this was pointing to fuel starvation of some type, either from the vac tank or carby.
So for the umpteenth time it was back to the resto shed, Grant would pull up, Ray would jump out, grab Bella the dog and open the gates. At least we had that part down pat.
Decided to tackle the carby before the vac tank, and glad we did, cause we fixed the majority of the problem. The distance from the top of the float to the base of the carby housing was way over the 1/2 inch that it should be. This was reset, we played around a bit with the air / fuel adjustment and hit the open road.
The proof in the pudding was that Grant said for the first time he could recall, Monty did not start surging on the road between Trafalgar and Yarragon. We still have a small problem that if pushed too long at 80 k's and above Monty starts to runs out of legs and loose power. I believe this is a minor adjustment still to be made, and according I will seek some advice on what to do.
We then went up Thorpe hill, a very steep climb out the back of Trafalgar and Monty pulled very well in top gear all the way.
So at the end of a "play " day, Monty was 7/8ths tamed, running smoother and quieter, and the next challenge will be to stretch his legs a bit more over 80 k's.
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