Problems with the animal????

[odogracing]

So we are in the process of putting another car with an animal motor.  I have heard they are having some fuel issues with animals running the restrictor plates.  Does anyone know if they have made a progress on this?  Has anyone experienced this?  I have been holding off buying the motor until I can confirm they have worked out all the bugs.

[CrewChief6]

Many Junior Animal motors are seeing problems, including popping, skipping, fading, etc. It appears to be restrictor plate-related, in combination with float level settings. Briggs is studying the issues and doing tests, but because the symptoms differ from track to track (because of configurations), it's difficult to pinpoint.

We can only hope they'll find a solution soon, and hopefully implement it by next season. But in the meantime, we should all keep track of problems and let your engine-builders know so they can work with Briggs to find a fix.

For our car, one thing we noticed is if our driver lets off the gas on turns, the fuel pools behind the restrictor plate and when he fires again, it pops. So one fix we can control is to have the driver keep the foot in the gas.

What are some other symptoms are others seeing?

[racemom2000]

We have a senior animal engine & haven't had any of those problems. From what we've seen, the above mentioned problems seem to be troublesome for the junior animals vs. senior. Something with the restrictor plate, people think.

I just wish the animals were a bit easier to start. They sure get you your exercise for the day....

[CrewChief6]

Confirmed. The problems are with Junior Animals and the three-hole restrictor plates (in combination with float levels). The Senior Animals have the one-hole plates, and those don't have the issues the Juniors are seeing. Troubleshooting is really difficult because the car can run really well at one track, and act up at another. Also, symptoms can be different from car to car.

As far as starting the animal, see Eric Rankine's post from earlier in the year. Very helpful. Thanks Eric.
http://www.usacracing.com/forum/index.php/topic,2286.0.html

I'll add this note that's helped our team. Driver should push the gas down a smidge when the car is being pushed off and with the switch off. Then turn on the switch when you've got it at a good speed. And don't forget to start up the motor before you go out. Animal doesn't like to go out cold.

[JMW23]

If this is a combination of restrictor and float level, is the float level to high or low and where should it be and how do you check it? We are new to animals and tested today and had a miss as he entered corners the longer we ran.

[CrewChief6]

Here's a good video by Briggs Racing. You can check the level with a caliper or a special float level tool.

http://www.briggsracing.com/en/videos/setting-float-height-on-your-walbro-pz-carburetor.aspx

[sfreitas20]

There really isn't a good answer to the question of where the float should be.  It seems like it changes all the time.  For example we had our car running perfectly on the Wednesday before the last race in Tampa with the float set about 750 but then without any changes to the car it was missing horribly at the Saturday practice session and I started raising it.  The miss went away at about 860, however it showed back up with about 8 laps to go during the Feature on Sunday (Luckily AJ had a big enough lead to hang onto for the win).  We have had it as high as 925 at the Tampa track.

My best piece of advice is to learn how to adjust that thing, get one of these http://fastermotors.net/Floatgauge.html to help with adjusting, and have some patience until they come up with a better way to slow down these JR Animals than the restrictor plates.

[JMW23]

Thanks guys! Now I have a place to start.

[CrewChief6]

Keep us posted. We're all groping in the dark on this one.

[RBurns17]

If anyone knows any go kart teams who run the animal I know they have experienced similar problems with the float. So they might be able to tell you something.

[sfreitas20]

I have asked some familiar with it from karting and basically they said to get used to adjusting it, or find out what settings work the best at each track and then have at least a float for each track so you just swap them out.  Some even carry additional carbs setup for certain tracks.

I have also heard some try to reduce the fuel flow into the carb, but Steve Baker had us try that here in Tampa with a plug in the fuel line with only a little hole in it but that didn't seem to help.

We even tested with a different intake manifold that turned the carb so it was straight backwards instead of at an angle to see if it helped, but it didn't.  We know that wouldn't have been legal, but if it worked maybe we could have suggested it to USAC as an option.

[dmmc]

I would highly recommend running an air filter with this carb.  Any issues that we have had with our senior animal have showed up after running without a filter, and have disappeared after thouroughly cleaning the carb.  I'm thinking about disassembling and cleaning the carb after every race weekend, just to be on the safe side.  As for starting issues, if you tell your driver not to even touch the gas pedal until the switch has been on for 2-3 seconds they start MUCH easier.  How much spewed oil are you all finding in your catch cans after a run? 

[sfreitas20]

We run an air filter on our Jr Animal, but it doesn't change anything with regards to this issue.  You aren't going to see the same issue with a Sr Animal as we are seeing with the Jr Animals.  We are just the lucky ones I guess.

Regarding the oil: I haven't measured it, but quite a bit.  I would estimate it to be at least a few ounces after a heat race, lower main and a feature (this is with our teams Jr Animal and Sr Animal).  I have also asked Karting people about this and they laughed and said a few ounces is nothing.  They said sometimes they will put 16 - 17 ounces in before a race day and are only draining 8 - 9 ounces out afterwards.

[sprintcar39]

I run just 13 ounces and rarely get any in my catch can.

[sfreitas20]

That could be it, we have always run 16 in ours.  Will try just 13 this week and see how it goes.