77 Westy high rpm hesitation

Find/Fix/Report Back

Moderators: Amskeptic, Sluggo

User avatar
Ronin10
Getting Hooked!
Location: Columbia City, Seattle, WA
Status: Offline

Re: 77 Westy high rpm hesitation

Post by Ronin10 » Thu Jul 11, 2019 6:33 am

GreenWesty83 wrote:
Wed Jul 10, 2019 12:24 pm
Thanks for the heads up! Are there any other units that are known better quality?
Not that I can speak to
Oscar: 1976 Sage Green Bus, Stock Motor, Solid Lifters, Manual Transaxle

JPower6210
I'm New!
Status: Offline

Re: 77 Westy high rpm hesitation

Post by JPower6210 » Tue Jul 16, 2019 5:33 am

Hi- I am admittedly a neophyte at all of this- and you have the experts weighing in. I did however suffer some similar problems when I first got my bus. Got it all tuned up, bought a pertronix unit, installed and had some issues at the high end. As an experiment, I went back to points and the problem disappeared. I really like the Pertronix set up, and run it in a couple of other vehicles, but since the points fixed the issue for me, I have been lazy and stuck with the points for now. I will try the Pertronix again, but it's low on the list.

Just a thought....

JP
1976 Chrome Yellow Westy - "Tallulah"

User avatar
Amskeptic
IAC "Help Desk"
IAC "Help Desk"
Status: Offline

Re: 77 Westy high rpm hesitation

Post by Amskeptic » Tue Jul 16, 2019 8:46 am

JPower6210 wrote:
Tue Jul 16, 2019 5:33 am
Hi- I am admittedly a neophyte at all of this- and you have the experts weighing in. I did however suffer some similar problems when I first got my bus. Got it all tuned up, bought a pertronix unit, installed and had some issues at the high end. As an experiment, I went back to points and the problem disappeared. I really like the Pertronix set up, and run it in a couple of other vehicles, but since the points fixed the issue for me, I have been lazy and stuck with the points for now. I will try the Pertronix again, but it's low on the list.

Just a thought....

JP
There is nothing lazy about using points. There is devotion to the gestalt. I think you may be on to something in suggesting a brief run with points. I have had a couple of weird Pertronix symptoms with customers, including high-speed misfire.
Colin
BobD - 1978 Bus . . . . . . . . . . . 112,660 miles
Chloe - 1970 bus . . . . . . . . . . . 206,845 miles
Naranja - 1977 Westfalia . . . . . 112,885 miles
Pluck - 1973 Squareback . . . . . . 55,570 miles
Alexus - 1991 Lexus LS400 . . . 78,899 miles

GreenWesty83
I'm New!
Status: Offline

Re: 77 Westy high rpm hesitation

Post by GreenWesty83 » Wed Jul 17, 2019 12:15 pm

JPower6210 wrote:
Tue Jul 16, 2019 5:33 am
Hi- I am admittedly a neophyte at all of this- and you have the experts weighing in. I did however suffer some similar problems when I first got my bus. Got it all tuned up, bought a pertronix unit, installed and had some issues at the high end. As an experiment, I went back to points and the problem disappeared. I really like the Pertronix set up, and run it in a couple of other vehicles, but since the points fixed the issue for me, I have been lazy and stuck with the points for now. I will try the Pertronix again, but it's low on the list.

Just a thought....

JP
I did have the issue with points at first. When the issue initially appeared during a road trip points were installed. I then installed new Pertronix hoping that would address the issue. It did not. However I don’t believe I ever tried NEW points and condenser.
I still have to put three more clicks on the cog and try that as well.
1977 Sage Westy
1968 Blue Bug

GreenWesty83
I'm New!
Status: Offline

Re: 77 Westy high rpm hesitation

Post by GreenWesty83 » Tue Jul 30, 2019 6:46 am

I was able to put three more clicks on the COG and give it three turns. I didn’t have time for a long drive. But did get it out and up to 60 mph. Haven’t noticed any hesitation as of yet. But I am going to get it out on the highway this week and really try it out.
Colin. I am curious as to how my engine would get this out of whack with the mixture. And as far as tuning goes. How often do I have to touch the AFM? And how do I test that it isn’t getting out of adjustment again?
1977 Sage Westy
1968 Blue Bug

User avatar
Amskeptic
IAC "Help Desk"
IAC "Help Desk"
Status: Offline

Re: 77 Westy high rpm hesitation

Post by Amskeptic » Tue Jul 30, 2019 3:51 pm

GreenWesty83 wrote:
Tue Jul 30, 2019 6:46 am
Colin. I am curious as to how my engine would get this out of whack with the mixture. And as far as tuning goes. How often do I have to touch the AFM? And how do I test that it isn’t getting out of adjustment again?

Over time, valve guides wear, piston rings wear, sensors shift their resistances (like additional restistance at the TS 2, grounds get more oxidized, system voltage deteriorates, valve cover gaskets may start to suck in air very subtle, oil filler cap/tube, dipstick hat gasket petrifies, blah blah blah, record your adjustments, and drive!
Colin
BobD - 1978 Bus . . . . . . . . . . . 112,660 miles
Chloe - 1970 bus . . . . . . . . . . . 206,845 miles
Naranja - 1977 Westfalia . . . . . 112,885 miles
Pluck - 1973 Squareback . . . . . . 55,570 miles
Alexus - 1991 Lexus LS400 . . . 78,899 miles

GreenWesty83
I'm New!
Status: Offline

Re: 77 Westy high rpm hesitation

Post by GreenWesty83 » Mon Aug 05, 2019 3:10 pm

Ok. Spent the weekend REALLY driving her around. Virtually no hesitation to speak of. Put a good 100 miles on her. Had one little blip anomaly at one point. But drove more afterward and did not repeat itself. Seems to be the issue is fixed!
After the adjust I noticed the idle was running high. Close to 2000rpm. Adjusted idle down to around 900-1000. Noticed that with idle adjusted down the next morning the engine had a hard time warming up. Sputtering a little. Turned screw a bit and it idled much better. Waited till engine was warm and brought idle back down again to the 1000rpm. Is this somewhat normal? Should I look at something else?
1977 Sage Westy
1968 Blue Bug

User avatar
Amskeptic
IAC "Help Desk"
IAC "Help Desk"
Status: Offline

Re: 77 Westy high rpm hesitation

Post by Amskeptic » Mon Aug 12, 2019 9:42 pm

GreenWesty83 wrote:
Mon Aug 05, 2019 3:10 pm
Noticed that with idle adjusted down the next morning the engine had a hard time warming up. Sputtering a little. Turned screw a bit and it idled much better.
Turned screw a bit which way? Which screw? Speed screw?

GreenWesty83 wrote:
Mon Aug 05, 2019 3:10 pm
Waited till engine was warm and brought idle back down again to the 1000rpm. Is this somewhat normal? Should I look at something else?
Idle speed and mixture must be adjusted warm only.

We have richer mixture now, correct?
We did it all at the cog (black plastic gear teeth), yes?

You now have a pig-rich cold mixture that should only last about 6 minutes.

There is more we can do ...
Colin
BobD - 1978 Bus . . . . . . . . . . . 112,660 miles
Chloe - 1970 bus . . . . . . . . . . . 206,845 miles
Naranja - 1977 Westfalia . . . . . 112,885 miles
Pluck - 1973 Squareback . . . . . . 55,570 miles
Alexus - 1991 Lexus LS400 . . . 78,899 miles

GreenWesty83
I'm New!
Status: Offline

Re: 77 Westy high rpm hesitation

Post by GreenWesty83 » Thu Sep 05, 2019 7:31 pm

Amskeptic wrote:
Mon Aug 12, 2019 9:42 pm
GreenWesty83 wrote:
Mon Aug 05, 2019 3:10 pm
Noticed that with idle adjusted down the next morning the engine had a hard time warming up. Sputtering a little. Turned screw a bit and it idled much better.
Turned screw a bit which way? Which screw? Speed screw?
Yes. The Bypass screw to adjust idle speed. The idle was too low when engine was cold, so I turned it counterclockwise to increase the speed so it would idle better cold.
Amskeptic wrote:
Mon Aug 12, 2019 9:42 pm
GreenWesty83 wrote:
Mon Aug 05, 2019 3:10 pm
Waited till engine was warm and brought idle back down again to the 1000rpm. Is this somewhat normal? Should I look at something else?
Idle speed and mixture must be adjusted warm only.

We have richer mixture now, correct?
We did it all at the cog (black plastic gear teeth), yes?

You now have a pig-rich cold mixture that should only last about 6 minutes.

There is more we can do ...
Colin
Yes, the mixture is richer now.
Cog has been adjusted per your instructions.

So Colin, I must apologize in advance for being so paranoid. But one of my worries is that the engine is damaged in some way (possibly due to over heating as the issue manifested towards the end of a long trip).
I worry that i had a vacuum leak or warped head or something that is being masked by the adjustment of the cog?
I also frequent Ratwell's page as well and have read the article in the FAQ regarding vacuum testing. I had done a test last year and thought the results were a bit low (he gives the range for a healthy stock engine to be 15"-18") mine at that time came in around 13". Which i thought might be indicative of a vacuum leak.
Tonight i was able to do another test on my engine. I wanted to report my results and have you weigh in with your thoughts

Tonight temp is 81* and I'm at 2550' elevation. I did a vacuum test and tested idle.
Stone cold engine, (well, 81*)
Vacuum: 15 inHg for about 15 sec, then dropped to 11 inHg
Idle: 700 rpm

Took bus on a good 15 min drive, highway speeds (55mph, slow highway), came home and tested again.
Vacuum: 15 inHg
Idle: 1100 rpm

So is this a healthy engine? Do i have to fear burning valves or anything like that?

So again, sorry if I am being way over the top. I have just heard stories of burning valves up and stuff by mistakenly masking up a vacuum leak or something. The bus is running beautifully however, and i want to take her camping soon, just making sure all my homework is done!!

Thanks!
1977 Sage Westy
1968 Blue Bug

User avatar
Amskeptic
IAC "Help Desk"
IAC "Help Desk"
Status: Offline

Re: 77 Westy high rpm hesitation

Post by Amskeptic » Fri Sep 06, 2019 7:25 am

GreenWesty83 wrote:
Thu Sep 05, 2019 7:31 pm
The bus is running beautifully however,

Enjoy ... :flower:
BobD - 1978 Bus . . . . . . . . . . . 112,660 miles
Chloe - 1970 bus . . . . . . . . . . . 206,845 miles
Naranja - 1977 Westfalia . . . . . 112,885 miles
Pluck - 1973 Squareback . . . . . . 55,570 miles
Alexus - 1991 Lexus LS400 . . . 78,899 miles

Post Reply