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Blow-by continues to get worse. Anyone else yet? Any oil in your air boxes? Have you pulled your oil fill cap while running?
Paxton guys - Any blow by?
- Thread starter Viper X
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Doug Supercharged Vipers
Enthusiast
Make certain the ventilation hoses are properly installed on the valve covers and intake; and surely no kinks. Verify the direction of the pcv valve.
How well does the engine run? Could you inspect the spark plugs anytime soon? See if you find one that may be fouled ...
Hope this helps ...
Doug Levin
How well does the engine run? Could you inspect the spark plugs anytime soon? See if you find one that may be fouled ...
Hope this helps ...
Doug Levin
I had big time blow by. There was a previous thread about this. I ended up using a catch can and it has done a great job, very nice and clean since then. I had oil all over the front of the engine and the plenum had a puddle. I really started noticing it after track days.
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Hi Guys. Thanks for the responses.
Art, unscrew the oil filler cap on the valve cover and start the engine. Don't rev it, just let it idle. Do you have a steady stream of vapor coming from it or do you have vacuum? You can check by putting a business card over it and see if it shows vacuum or simply blows off.
Doug, thanks for the response. Engine was running very well until a couple of days ago. Now it is puffing smoke out of the catch can. I previously had oil in the air box and have had oil in the air box since the new heads were installed. I got tired of this, so I installed a catch can directly from one of the valve covers - the one that goes to the air box - and replaced the PCV valve (no problem but wanted to be sure) and it is functioning well. No kinks or hose problems.
ViperGMC, I remember your thread. I think I was the one that suggested the catch can. Initially, it worked for me too. Problem is, I have so much blow by now that it's puffing out of the catch can. I hope you are not next.
The engine has only 25,000 mile on it, 14,000 with the Paxton. I've changed the oil every 2500 and haven't really driven it that hard. It uses only a total of about 1/2 quart of oil in 2500 miles and of that, about 6 ounces is found in the catch can. Engine vacuum varies at idle from 16 to 19 depending upon the temperature and can vary that much in one afternoon, so I'm not sure what's up with that. I don't expect a ring problem, but do think that the valve guides or stem seals, or both are failing or have failed. Maybe a burnt valve or cracked piston?
Car is in the shop, again. I'll let you guys know. Fortunately, I have the GTS to drive.
Dan
Art, unscrew the oil filler cap on the valve cover and start the engine. Don't rev it, just let it idle. Do you have a steady stream of vapor coming from it or do you have vacuum? You can check by putting a business card over it and see if it shows vacuum or simply blows off.
Doug, thanks for the response. Engine was running very well until a couple of days ago. Now it is puffing smoke out of the catch can. I previously had oil in the air box and have had oil in the air box since the new heads were installed. I got tired of this, so I installed a catch can directly from one of the valve covers - the one that goes to the air box - and replaced the PCV valve (no problem but wanted to be sure) and it is functioning well. No kinks or hose problems.
ViperGMC, I remember your thread. I think I was the one that suggested the catch can. Initially, it worked for me too. Problem is, I have so much blow by now that it's puffing out of the catch can. I hope you are not next.
The engine has only 25,000 mile on it, 14,000 with the Paxton. I've changed the oil every 2500 and haven't really driven it that hard. It uses only a total of about 1/2 quart of oil in 2500 miles and of that, about 6 ounces is found in the catch can. Engine vacuum varies at idle from 16 to 19 depending upon the temperature and can vary that much in one afternoon, so I'm not sure what's up with that. I don't expect a ring problem, but do think that the valve guides or stem seals, or both are failing or have failed. Maybe a burnt valve or cracked piston?
Car is in the shop, again. I'll let you guys know. Fortunately, I have the GTS to drive.
Dan
So do I take it that prior to new heads being installed you had no pullover issue?
I see no reason that at idle that the pcv system would not create a vacuum in the crankcase. It sounds like something is wrong with the pcv system. The only time the Paxton should affect it is under boost (and then the check valve should prevent the boost pressure from going into the engine), making the make-up air line the primary crankcase vent (note vented to the clean side of the airbox).
The make up air line should only outflow when the inlet is under pressure. Rather than removing the oil fill cap it would be better to remove the make-up air hose and verify that it has a slight suction when the intake is under a vacuum.
I see no reason that at idle that the pcv system would not create a vacuum in the crankcase. It sounds like something is wrong with the pcv system. The only time the Paxton should affect it is under boost (and then the check valve should prevent the boost pressure from going into the engine), making the make-up air line the primary crankcase vent (note vented to the clean side of the airbox).
The make up air line should only outflow when the inlet is under pressure. Rather than removing the oil fill cap it would be better to remove the make-up air hose and verify that it has a slight suction when the intake is under a vacuum.
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Cris,
Prior to the Paxton / Heads install, which was done at the same time, I had no blow-by. The engine had 10,000 miles on it so it was well broken in.
The reason that the pcv system doesn't create a vacuum in the crankcase at idle is not clear, yet. Likely the 14,000 miles spend "under boost" even though only occasional, have caused some damage to the cylinder walls, piston ring lands, rings or the cast pistons themselves. The engine should be out tomorrow and a closer inspection will reveal the problem. The preliminary tests performed today indicated that the air was "blowing by" the pistons and into the crank case from both halves of the engine, past the pistons themselves. There was no indication of any valve problems, as I had hoped.
Prior to the Paxton / Heads install, which was done at the same time, I had no blow-by. The engine had 10,000 miles on it so it was well broken in.
The reason that the pcv system doesn't create a vacuum in the crankcase at idle is not clear, yet. Likely the 14,000 miles spend "under boost" even though only occasional, have caused some damage to the cylinder walls, piston ring lands, rings or the cast pistons themselves. The engine should be out tomorrow and a closer inspection will reveal the problem. The preliminary tests performed today indicated that the air was "blowing by" the pistons and into the crank case from both halves of the engine, past the pistons themselves. There was no indication of any valve problems, as I had hoped.
If you have no crankcase depression at idle with an appropriate amount of inlet depression, then there is something wrong with the pcv setup (stuck valve, valve installed backwards, kinked hose, disconnected hose (easy to disconnect at the Tee at the rear of the manifold), etc.). No way should you have enough blowby at idle to overcome the pcv system.
In case you continue to question cylinder leakage the best way to check for cylinder condition is a compression and a leakdown test. Combined they should indicate the health of the piston and valve sealing.
In case you continue to question cylinder leakage the best way to check for cylinder condition is a compression and a leakdown test. Combined they should indicate the health of the piston and valve sealing.
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Engine out and on stand. #8 cylinder looking like the one. Lots of oil / black discoloration on the exhaust valve as seen throught the port. Heads off tomorrow. More then.
DB/Paxton SRT-10
Viper Owner
I wonder, is your repair work covered by warranty? My guess is no due to the mods.
Darel
Darel
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DB/Paxton SRT-10,
Good question, though not where I'm headed. The cast pistons in our engines will not handle boost well or for very long. A warranty rebuild would only likely delay the inevitable, going with all forged internals, which is now the direction I plan to take. You can't make big horsepower with these newer cars. They just aren't as strong as the earlier all forged Viper engines. Too bad.
Last nights phone call from my mechanic indicated that the piston lands at the oil rings on the first two pistons removed from the block had begun to fail. Had I waited much longer these pistons would likely have come apart and I would have needed a new block, crank, etc., etc.
Our "cracked cap powdered metal rods" aren't the greatest either with a forced induction, high horsepower engine.
I hope, for everyone else's sake that my engine is the exception, but it likely isn't. Time will tell.
Dan
Good question, though not where I'm headed. The cast pistons in our engines will not handle boost well or for very long. A warranty rebuild would only likely delay the inevitable, going with all forged internals, which is now the direction I plan to take. You can't make big horsepower with these newer cars. They just aren't as strong as the earlier all forged Viper engines. Too bad.
Last nights phone call from my mechanic indicated that the piston lands at the oil rings on the first two pistons removed from the block had begun to fail. Had I waited much longer these pistons would likely have come apart and I would have needed a new block, crank, etc., etc.
Our "cracked cap powdered metal rods" aren't the greatest either with a forced induction, high horsepower engine.
I hope, for everyone else's sake that my engine is the exception, but it likely isn't. Time will tell.
Dan
Doug Supercharged Vipers
Enthusiast
Dan,
Would I be guessing correctly the damage to the pistons were found on the right side of the block (even numbers?)
Regards,
Doug
This is interesting, I wonder what some of the longer term effects of the Paxton will be on these engine components. My car is running fine and still strong. I have 20K miles with the SC and at least 4+k miles on the track. I have had a growing concern about my engine with all my track time that I did this year. Issues with the OEM oil pan (which I upgraded), oil blow by (installed a catch can), cast pistons (soon forged), powder rods (soon forged) are a few things that are prompting to open it up. I thought over X-Mas would be a good time to tear into the motor and see what’s been happening. The block and crank are good for 1200 WRHP but the piston for sure and some what the rods are definitely the week link for going to more HP/boost.
I think we are only running into this because we are HP junkies. I am still very impressed that it is even possible to get 850WRHP on 93 octane. How cool is that, my daily driver can do (soon to be) 850 RWHP on pump gas. I am very confident that strictly street driving the standard Paxton set up will never have an issue. Anyway, I think we are all learning a lot about our engines and we will only get better. The motor is coming out next week, we’ll see.
I think we are only running into this because we are HP junkies. I am still very impressed that it is even possible to get 850WRHP on 93 octane. How cool is that, my daily driver can do (soon to be) 850 RWHP on pump gas. I am very confident that strictly street driving the standard Paxton set up will never have an issue. Anyway, I think we are all learning a lot about our engines and we will only get better. The motor is coming out next week, we’ll see.
Kai SRT10
Enthusiast
This was ultimately my conclusion as well. A warranty rebuild wouldn't do what I needed it to. When my engine gets rebuilt, it will be with upgraded pistons, rods, etc.
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Hi Doug,
Yes, I'm told the first two pistons out of the block were numbers 10 and 8, so you are right. I am planning to "visit" my car and take some pics next week, so I'll know more then. I just need to learn how to post pics here.
ViperGMC,
If your engine follows mine, the oil blow by is the first step and the catch can solves the problem, for a while. I tracked my car too and spend some limited time at the drags. I would guess that the new stage III heads, roller rockers and resulting higher rpms available with the rev limiter raised probably helped my pistons go south faster than most.
Also, I was getting 9 psi max boost, though Paxton reports a max of only 7.5 psi, which I now know to be too much for these engines with cast pistons. I think you are doing the right thing checking yours out, and while it's down, make the changes before they cost you a block and crank. I'll probably up the displacement too while it's apart.
Kai.
Good decision. You run your car like I run mine. Have you considered running the Silver State next spring?
Good luck,
Dan
Yes, I'm told the first two pistons out of the block were numbers 10 and 8, so you are right. I am planning to "visit" my car and take some pics next week, so I'll know more then. I just need to learn how to post pics here.
ViperGMC,
If your engine follows mine, the oil blow by is the first step and the catch can solves the problem, for a while. I tracked my car too and spend some limited time at the drags. I would guess that the new stage III heads, roller rockers and resulting higher rpms available with the rev limiter raised probably helped my pistons go south faster than most.
Also, I was getting 9 psi max boost, though Paxton reports a max of only 7.5 psi, which I now know to be too much for these engines with cast pistons. I think you are doing the right thing checking yours out, and while it's down, make the changes before they cost you a block and crank. I'll probably up the displacement too while it's apart.
Kai.
Good decision. You run your car like I run mine. Have you considered running the Silver State next spring?
Good luck,
Dan
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GR8 ASP,
Yes, I believe that the higher rpm increased the boost as noted above. It also increased the peak hp, and likely accelerated the piston wear.
ViperGMC,
West Coast Viper (and others?) can raise your rev limit through the use of their computer interface / tuning equipment with your stock computer. My rev limiter was raised to 6400 and I still "bumped" it once in a while. At my stock setting of 6200, I hit it all the time. The car just wound up so quickly.
Dan
Yes, I believe that the higher rpm increased the boost as noted above. It also increased the peak hp, and likely accelerated the piston wear.
ViperGMC,
West Coast Viper (and others?) can raise your rev limit through the use of their computer interface / tuning equipment with your stock computer. My rev limiter was raised to 6400 and I still "bumped" it once in a while. At my stock setting of 6200, I hit it all the time. The car just wound up so quickly.
Dan
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Gentlemen,
Tear down results are in. 7 of 10 pistons had ring land failures, i.e., these pistons came apart in between the rings. Chunks of the ring lands had failed and could be removed by hand. Piston #8 had part of it's oil ring bent downward and scratched the cylinder liner. Fortunately, all of these failed / broken parts were still contained inside the cylinders. If any of these metal parts had fallen into the oil pan, what an expensive mess it could have made.
No pattern of detonation on the pistons. Rods were fine, in fact the rod bearings looked new. Carbon on the piston tops was minimal. Block OK.
You guys running Paxton's on your cast piston engines - read stock - beware. 14,000 miles with the Paxton and 7 of 10 pistons failed. These pistons just won't hold up to the boost and heat created by the supercharger.
Paxton should lower the boost pressure on their units and it sure would be nice if DC went back to all forged internals, among other things.
Dan
Tear down results are in. 7 of 10 pistons had ring land failures, i.e., these pistons came apart in between the rings. Chunks of the ring lands had failed and could be removed by hand. Piston #8 had part of it's oil ring bent downward and scratched the cylinder liner. Fortunately, all of these failed / broken parts were still contained inside the cylinders. If any of these metal parts had fallen into the oil pan, what an expensive mess it could have made.
No pattern of detonation on the pistons. Rods were fine, in fact the rod bearings looked new. Carbon on the piston tops was minimal. Block OK.
You guys running Paxton's on your cast piston engines - read stock - beware. 14,000 miles with the Paxton and 7 of 10 pistons failed. These pistons just won't hold up to the boost and heat created by the supercharger.
Paxton should lower the boost pressure on their units and it sure would be nice if DC went back to all forged internals, among other things.
Dan
Dan, good comments but I notice your performance numbers indicate about 100 RWHP more than the stock Paxton kit. That is significant and may be the cause for a shortened life. Detonation is only one factor. More horsepower like you have requires more average cylinder pressure (by definition) and usually higher peak pressures and temperatures. Without detonation the temperature and pressure is what would fatigue the top land.
Did you perform oil analysis to see if there was excess aluminum in the oil indicating premature wear?
Did you perform oil analysis to see if there was excess aluminum in the oil indicating premature wear?
I am pulling my engine in the AM. I have 20K on the stock Paxton kit. Should be interesting to see what my internal look like. I am suffering from no issues, the engine sounds fine and is running strong. I will report my findings as they come in as well. This is an excellent discussion
Y2K5SRT
Enthusiast
So, what else do you have planned for your car while the engine is out? I read about the pistons/rods - any other upgrades planned during that time? Head work? Cam? Inquiring minds want to know...
Oh yeah, and we are looking forward to what you find when you open up that motor. Thanks in advance!
I am planning on doing an entire host of items while the car is on the rack. Forged rods and pistons (.03 over), stage III heads, T&D rockers, 12 psi pulley, RSI fuel rail and pumps, aluminum flywheel, ATI damper, Balenger herders, reprogrammed PCM, new plug wires, stainless brakes lines, brake cooling ducts, chrome calipers, new rotors/pads, new hood pad, new Eibach springs and finally new air in all the tires.
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Dan,
Sorry to hear about the engine problems. After a ride in that beast I think you need some more power now. I just sold my House in Corona and am moving back to Aliso. I'm starting to look for my Vipe now so I can part the Z. Makes me think twice about bolting the blower on without the pistons. I'll be giving you a call when I'm close to delivery.
Mike
Sorry to hear about the engine problems. After a ride in that beast I think you need some more power now. I just sold my House in Corona and am moving back to Aliso. I'm starting to look for my Vipe now so I can part the Z. Makes me think twice about bolting the blower on without the pistons. I'll be giving you a call when I'm close to delivery.
Mike
DSR207
Enthusiast
Quote:
"I am planning on doing an entire host of items while the car is on the rack. Forged rods and pistons (.03 over), stage III heads, T&D rockers, 12 psi pulley, RSI fuel rail and pumps, aluminum flywheel, ATI damper, Balenger herders, reprogrammed PCM, new plug wires, stainless brakes lines, brake cooling ducts, chrome calipers, new rotors/pads, new hood pad, new Eibach springs and finally new air in all the tires."
WOW ...Do mine next 
?
"I am planning on doing an entire host of items while the car is on the rack. Forged rods and pistons (.03 over), stage III heads, T&D rockers, 12 psi pulley, RSI fuel rail and pumps, aluminum flywheel, ATI damper, Balenger herders, reprogrammed PCM, new plug wires, stainless brakes lines, brake cooling ducts, chrome calipers, new rotors/pads, new hood pad, new Eibach springs and finally new air in all the tires."
WOW
...Do mine next ?Funny you should ask. I do run a Viper charity call V.I.P.E.R.W.H.P. that is available to all Viper owners that are in need. To qualify you must show that your Viper is malnourished and that if it was not for the dinette set or window treatments you would have spent the $$ on the necessary upgrades.
You have access to a complete shop with lift and all the tools you need. Plus expert assistance and you will get your hands dirty. You probably need to live near Nashville too.
You have access to a complete shop with lift and all the tools you need. Plus expert assistance and you will get your hands dirty. You probably need to live near Nashville too.
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GR8 ASP:
Yes, the additional hp was attributed to the Stage III heads, headers and exhaust. Many Paxton equipped SRT-10's make 650 rwhp without any other mods. I added the heads and headers in hopes of flowing more air, making more hp and keeping things cooler - hoping for longer engine life. I bought the water / **** injection kit a couple of months ago but just haven't gotten around to installing it. I suspect it would help any Paxton equipped car run cooler and avoid some heat related problems. The tune was conservative and I used the Paxton equipped pulley, so I thought I was getting the correct amount of boost.
ViperGMC:
I look forward to hearing your tear down results.
Hi Mike:
Yes, I need more power. To many of us, horsepower is like a drug - I see that I'm not alone. When the engine goes back together, and that is happening now, it will be even more "beastly". Here are some of the mods, JE forged pistons + , 4.125 Darton wet liners, Oliver rods, Arp bolts and studs throughout, proprietary solid lifter cam, Stage IV heads, ATI keyed crankshaft dampener, a bunch of machine work, GTS-R double roller timing set, AEM engine management system, water/ **** injection, larger injectors, Mcleod twin disk clutch / billet pp, etc.
We are shooting for 900 + rwhp with the Paxton. We should be around 530 cubic inches. Boost can now go up a bit, so we shouldn't have too much trouble making this.
Dan
Yes, the additional hp was attributed to the Stage III heads, headers and exhaust. Many Paxton equipped SRT-10's make 650 rwhp without any other mods. I added the heads and headers in hopes of flowing more air, making more hp and keeping things cooler - hoping for longer engine life. I bought the water / **** injection kit a couple of months ago but just haven't gotten around to installing it. I suspect it would help any Paxton equipped car run cooler and avoid some heat related problems. The tune was conservative and I used the Paxton equipped pulley, so I thought I was getting the correct amount of boost.
ViperGMC:
I look forward to hearing your tear down results.
Hi Mike:
Yes, I need more power. To many of us, horsepower is like a drug - I see that I'm not alone. When the engine goes back together, and that is happening now, it will be even more "beastly". Here are some of the mods, JE forged pistons + , 4.125 Darton wet liners, Oliver rods, Arp bolts and studs throughout, proprietary solid lifter cam, Stage IV heads, ATI keyed crankshaft dampener, a bunch of machine work, GTS-R double roller timing set, AEM engine management system, water/ **** injection, larger injectors, Mcleod twin disk clutch / billet pp, etc.
We are shooting for 900 + rwhp with the Paxton. We should be around 530 cubic inches. Boost can now go up a bit, so we shouldn't have too much trouble making this.
Dan
Engine came out today. I have not pulled the heads off yet but there are no signs of any problems. The high pressure hose fitting on the power steering pump was leaking. Undoubtedly it was damaged when I pushed and bent the hose back to make room for the intercooler on installation. Belts good, hardware tight, small leak from the oil feed line to the Paxton, flywheel had some hot spots. We will see when the heads come off tomorrow, but I would not expect anything bad based on what I have seen so far. Maybe the 650-680 RWHP threshold for safe engines is accurate, but I don’t want to speak to soon. One thing for sure, we are the long term testers for this application.
