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Interesting Vacuum Pump issue
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DRR Sportsman
Picture of Mike Nitzsche
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I think there is merit to the stuck vanes theory, worth a look. I'm thinking though, that your engine is not sealed up well. My Moroso 4 vane pump pulls 6-7 at idle with the bleed closed and my Barnes 5 stage dry sump pulls 20+ at idle with the bleed closed. I've sucked intake gaskets and the idle can go up or down and be pretty inconsistent.
 
Posts: 1364 | Location: Lansing,Mi | Registered: March 20, 2007Reply With QuoteReport This Post
DRR Trophy
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I'm not going to comment about Mike's posts, but the picture of him with the malibu wagon does seem to make it on these posts quite often.

Mike is right about the intake gasket deal, i had one blow out exaclty as Mike calls it, bottom of #8 intake port. Ran the car like this for months and 6 or 7 races, i had funky runs usually late in eliminations where my light would be 0.700 and my 60' would be sub 0.500 or something stupid along those lines. A few times i got re-runs but later on in the problem i just gave up asking cause i felt stupid about it. The exhaust pointed straight down behind the front tires. Only smoked when the motor went from idle to wide open, the car left from an idle using a starting line enhancer, never a 3 step. Chased it for several races and months till i decided to put new lifters in, removed the intake and that gasket was pushed out like Mike talks about. I had to call one of the timing computer companies and talk to them about the issue before i really convinced myself of what was going on. It happens.

If you don't have vacuum at an idle that doesn't seem to be that much of an issue, but if its milking the oil with a functioning vacuum pump its too rich at an idle. Not sure if mine makes vacuum at an idle or not, as long as you have vacuum going down the track, you should be fine. Remove the inlet hose to the pump at an idle and see if its pulling vacuum, if it is the pump is working at an idle. Could also remove the other side and see if its discharging to the catch can. If you have vacuum on the inlet or if you have air flow out the discharge the pump is working. Some other things to check:

1. Poor crankcase seal somewhere. Pan, valve cover, timing cover, etc.
2. Speed of the pump, is it spinning 50% of crank speed? Can you speed it up? The pump has a 4000 RPM limit based on Moroso's recommendation. If you turn 8000 on the regular you are stuck at 50% but if your top RPM is lower than 8000 rpm you have room to increase the speed of your vacuum pump.
3. Ring seal is bad. You'll need leak it down to figure out what cylinders are an issue.
4. Your pump is a 3 vane possibly and your son's is a 4 vane. Check part numbers to verify. The 4 vanes are better and pull harder.

My money is on the idle is way too rich. Good luck.
 
Posts: 375 | Location: Pride, La | Registered: April 18, 2006Reply With QuoteReport This Post
DRR Top Comp
posted Hide Post
quote:
Originally posted by Mike Rietow:

Notice I never bring it up.



Shake head


.
Dave



F J B

 
Posts: 4467 | Location: Earth | Registered: February 08, 2006Reply With QuoteReport This Post
DRR Pro
Picture of chasracer
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quote:
Originally posted by Triple Nickel:

My money is on the idle is way too rich. Good luck.


It could be a possibility that it is rich but not crazy rich. I base that on cutting last season's plugs during the winter and none of the insulators had any indication of excessive fuel. I pulled all of the plugs today just to have a quick look and there isn't any one cylinder that appears to be off which if the intake gasket is gone, I would at least expect to see some additional oil? I am going to check the carb as I mentioned before and as to the pump operating - yes it does function at higher rpm. I plan on verifying the drive ratio which might be a possible answer. OR - should I simply not concern myself with not having any vacuum to speak of at idle? (1000-1100)
 
Posts: 1135 | Location: The problem is not the problem. The problem is your attitude about the problem. Savvy?” ~~ Captain Jack Sparrow ~~ | Registered: August 21, 2000Reply With QuoteReport This Post
DRR Pro
Picture of chasracer
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The only proper way to read an alky (methanol) spark plug is to cut the threaded body off of it and view the full length of the insulator.


Save on Fuel - GetUpside - https://upside.app.link/jE7eqmHc2z
 
Posts: 1135 | Location: The problem is not the problem. The problem is your attitude about the problem. Savvy?” ~~ Captain Jack Sparrow ~~ | Registered: August 21, 2000Reply With QuoteReport This Post
DRR Top Comp
posted Hide Post
quote:
Originally posted by imakehp:
quote:
Originally posted by Mike Rietow:

Notice I never bring it up.



Shake head


The problem is accountability. It's bad enough elected officials who've normalized immoral, aren't answerable.

No rule of law, no civilization.

It's way bigger than one drag race.
 
Posts: 9398 | Location: Madeira Beach Fl. | Registered: June 12, 2018Reply With QuoteReport This Post
DRR Sportsman
posted Hide Post
quote:
Originally posted by chasracer:
quote:
Originally posted by Triple Nickel:

My money is on the idle is way too rich. Good luck.


It could be a possibility that it is rich but not crazy rich. I base that on cutting last season's plugs during the winter and none of the insulators had any indication of excessive fuel. I pulled all of the plugs today just to have a quick look and there isn't any one cylinder that appears to be off which if the intake gasket is gone, I would at least expect to see some additional oil? I am going to check the carb as I mentioned before and as to the pump operating - yes it does function at higher rpm. I plan on verifying the drive ratio which might be a possible answer. OR - should I simply not concern myself with not having any vacuum to speak of at idle? (1000-1100)


My money is on idle too rich as well. It likely wouldn’t show up on a spark plug, a rich idle on methanol will just keep the plug looking like brand new, when you read it you’re seeing the under load conditions.

How much methanol does it use per run?
 
Posts: 715 | Location: Upstate NY | Registered: July 02, 2013Reply With QuoteReport This Post



DRR Pro
Picture of CURTIS REED
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Being really rich on Methanol would have a lot of blowby at idle also making it hard for the pump to keep up. Mine usually has about 5 inches at idle and I'm on Methanol. It's a small block car though, Star pump.



____________________________
2017 and 2018 Osage Casinos Tulsa Raceway Park No-Box Champion

2018 Div4 Goodguys Hammer award winner
 
Posts: 2948 | Location: KIEFER, OK. | Registered: August 17, 2007Reply With QuoteReport This Post
DRR Pro
Picture of chasracer
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Per lap is about 1.5-1.75 - varies a bit depending on depth of staging lanes I suppose. I have never measured it just prior to a pass and then just after.

I have a STAR on the dragster and that one always has about 4.5-5 inches at idle, set for 12-13 inches max. Someone mentioned different pumps and how they operate.


Save on Fuel - GetUpside - https://upside.app.link/jE7eqmHc2z
 
Posts: 1135 | Location: The problem is not the problem. The problem is your attitude about the problem. Savvy?” ~~ Captain Jack Sparrow ~~ | Registered: August 21, 2000Reply With QuoteReport This Post
DRR S/Pro
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chasracer

Plug readings have nothing to do with idle mixture rich/lean conditions.
If you are milking the oil your tune is too rich, the question here is, is it rich at WOT or idle, either way a properly tuned alky motor won't milk the oil with or without a vac pump! Some racers tune idle to be rich to provide additional cooling to the motor when it is hot and or double entering.
You already proved the vac pumps works at idle when you cleaned it but after a few runs it stops, so as I already mentioned the milky oil is causing the vanes to stay/stick closed at low rpm, and the cooler the air temps are the worse this is likely to become. You can offset this issue by spinning the pump faster but you still should fix the milking issue. Also get the oil hot, alky boils at 149 F, this will help milking also.
 
Posts: 2157 | Location: Tewksbury, MA,USA | Registered: November 03, 2000Reply With QuoteReport This Post
DRR S/Pro
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Hi Charlie:

Good point about the RP and methanol, didn't know that they don't play well together.

Bob

ps:

Have no idea what M.R. posts, blocked him a L O N G time ago.
 
Posts: 3083 | Location: Lakeside, Ca | Registered: February 15, 2003Reply With QuoteReport This Post
DRR Top Comp
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It's a process of elimination.

It's like taking a multiple choice test.

All The op should have to do, to test the sticking vanes theory, is pull the hose off the top of the valve cover and spray brake cleaner down the throat of the hose.

Start the car.

You know every aspect of the fuel mixture is rich. sb using 2 gallons a lap, tells you this.

I tried to tell the op how to tune this thing but he knew better, so I won't be making that mistake again.

I will say it's obvious he is pouring way too much fuel down its throat.
 
Posts: 9398 | Location: Madeira Beach Fl. | Registered: June 12, 2018Reply With QuoteReport This Post
DRR S/Pro
posted Hide Post
quote:
Originally posted by Mike Rietow:

All The op should have to do, to test the sticking vanes theory, is pull the hose off the top of the valve cover and spray brake cleaner down the throat of the hose.

Start the car.



Go back to the first post and read it! Big Grin
 
Posts: 2157 | Location: Tewksbury, MA,USA | Registered: November 03, 2000Reply With QuoteReport This Post
DRR Top Comp
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Are we to speculate on how the OP is cleaning the pump, or are we to wait for the OP to confirm how he is cleaning the pump?

Are we here to give the OP a hand, or play a game of gotcha?

Grow up would ya? Step outside that box you're in.

It's a simple process of elimination.
 
Posts: 9398 | Location: Madeira Beach Fl. | Registered: June 12, 2018Reply With QuoteReport This Post



DRR S/Pro
posted Hide Post
quote:
Originally posted by Mike Rietow:
Are we to speculate on how the OP is cleaning the pump, or are we to wait for the OP to confirm how he is cleaning the pump?

Are we here to give the OP a hand, or play a game of gotcha?

Grow up would ya? Step outside that box you're in.

It's a simple process of elimination.


What an Ultra Maroon! Razz
 
Posts: 2157 | Location: Tewksbury, MA,USA | Registered: November 03, 2000Reply With QuoteReport This Post
DRR Pro
Picture of Alaskaracer
posted Hide Post
quote:
Originally posted by chasracer:
The only proper way to read an alky (methanol) spark plug is to cut the threaded body off of it and view the full length of the insulator.


I was taught that the insulator is pretty much a no go on methanol since they typically don't leave the carbon ring that gas does. I look at the base ring, and inside of the threads, and the ground strap. Look for a 3/4ish turn of color on the base ring, heat about two to three threads deep and timing mark about halfway on the bend of the electrode....


Mark Goulette
Owner/Driver of the Livin' The Dream Racing dragster
www.livinthedreamracing.com
"Speed kills but it's better than going slow!"
Authorized Amsoil Retailer
 
Posts: 1468 | Location: Back home in Alaska! | Registered: February 13, 2011Reply With QuoteReport This Post
DRR Pro
Picture of chasracer
posted Hide Post
quote:
Originally posted by Coloradoracer:
quote:
Originally posted by chasracer:
The only proper way to read an alky (methanol) spark plug is to cut the threaded body off of it and view the full length of the insulator.


I was taught that the insulator is pretty much a no go on methanol since they typically don't leave the carbon ring that gas does. I look at the base ring, and inside of the threads, and the ground strap. Look for a 3/4ish turn of color on the base ring, heat about two to three threads deep and timing mark about halfway on the bend of the electrode....


All correct, I look at the same items.

As you said there really is no carbon ring to go by. That's the reason I take a set and cut the threads completely off with a cutoff tool and look at the entire insulator. On mine at least, I am simply looking for any signs of thermal change near the bottom of the insulator. On a gas plug if it's rich it will turn almost black. Looking at methanol there is a color difference but it's more like a white to off-white, you have to look at it with a strong light source to see it well. When we have been out in the weeds on too much fuel, I can't discern any difference at all.

I haven't tried it yet but has anyone had any luck using a bore scope to check the manifold/head gasket? If the gasket has sucked in it should be obvious but if it went towards the valley I'm not sure if it can be spotted?


Save on Fuel - GetUpside - https://upside.app.link/jE7eqmHc2z
 
Posts: 1135 | Location: The problem is not the problem. The problem is your attitude about the problem. Savvy?” ~~ Captain Jack Sparrow ~~ | Registered: August 21, 2000Reply With QuoteReport This Post
DRR Top Comp
posted Hide Post
Take a infrared Temp gun to each header tube.

If you have one tube significantly cooler than the rest, that'll tell you the fuel isn't making it into the chamber there, correct?

If they're all the same or thereabouts, you move on, correct?
 
Posts: 9398 | Location: Madeira Beach Fl. | Registered: June 12, 2018Reply With QuoteReport This Post
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