Have a set of XE262AH comp cams and Beehive 26113-16 springs installed in a 97 Mustang with the PI heads. The Passenger side cam is making a tapping noise and at first the tapping noise was at all RPM and dealer said three would not pump up with oil. So the dealer replaced the three they suspected of being the issue (although, I though you should do all eight) Now they are telling me that the tapping noise and oil issue is at higher RPMs. The dealer did not tell me if the issue was with the same lash valve adjusters that were replaced. Does not seem to be something simple like air in the lash adjusters. The Driver side head seems to run perfect. Any suggestions on this issue??? Has anyone experienced this problem with this set up? Ford seems incapable of fixing the issue...
262AH Comp CAMS- Lash adjuster pump up issue at Higher RFM
- Thread starter SleepyGreen97
- Start date
trinity_gt
10 Year Member
Were the cams degreed when they were installed?
If the driver's side is quiet and the passenger side is making a racket I'd suspect PTV as a possible source of the noise & would pull the front cover and verify the cam timing. If necessary, have them degreed to verify correct installation.
Will the cam timing effect the oil pressure in some of the valves?
Dealer is now telling me that they questioning the Oil Pump Pressure and the area effected is the last part of the engine to recieve oil. I am going to ask them to perform a pressure test and see if that is a problem although I really think its not an issue. The car ran great before they worked on it and only one side of the engine is effected. So my question is if the Timing is off would it effect three valves from pumping up with oil at higher RPM and then causing the tapping valve noise? Thank you for the help!!!!!
Dealer is now telling me that they questioning the Oil Pump Pressure and the area effected is the last part of the engine to recieve oil. I am going to ask them to perform a pressure test and see if that is a problem although I really think its not an issue. The car ran great before they worked on it and only one side of the engine is effected. So my question is if the Timing is off would it effect three valves from pumping up with oil at higher RPM and then causing the tapping valve noise? Thank you for the help!!!!!
trinity_gt
10 Year Member
When hydraulic lash adjusters "pump up" it means they act as miniature hydraulic rams and actually hold the valve open bit. Pumped-up HLAs don't tap because there's zero clearance in the valve train.
Honestly, I think you need to find another place to work on the car. The dealer sounds clueless.
Honestly, I think you need to find another place to work on the car. The dealer sounds clueless.
wmburns
SN Certified Technician
Is this a 97 NPI bottom end mated to PI heads? If so, doesn't this reduce the PTV clearance compared to stock combinations?
Could the combination of a higher lift cam and less clearance be causing PTV contact?
Could the combination of a higher lift cam and less clearance be causing PTV contact?
^ I don't think so burns. It's not the lift that is the problem anyways it's where the intake centerline lies. You could have PTV with a 0.500" cam that had a 105* intake centerline, but not have PTV with a 0.600" cam that had a 112* intake centerline. IIRC when PTV occurs on a modular 2V the valve actually contacts the piston near the edge so a piston with a slightly smaller dish (NPI) shouldn't be a problem. Also the 262's dont have a very aggressive intake centerline.
That said, I've heard Ford cam gears can be off by as much as +/-5*. Add to that the possibility that the Comp Cams may be off by +/- 3 * and you potentially have a situation where the cam is advanced 8* on one bank. I'd think that would most definitely cause PTV. That's why its so important, like you said, to properly degree cams when installing them.
That said, I've heard Ford cam gears can be off by as much as +/-5*. Add to that the possibility that the Comp Cams may be off by +/- 3 * and you potentially have a situation where the cam is advanced 8* on one bank. I'd think that would most definitely cause PTV. That's why its so important, like you said, to properly degree cams when installing them.
nyuk98gt
15 Year Member
The Comp Cams are not "off", they are ground with 4 degrees of advance.
N8Dogg98, you are right and Mr. Burns is right (as usual). The longer duration is what causes PTV clashes. Degreeing the cams is a must even with a mild cam.
Chris
N8Dogg98, you are right and Mr. Burns is right (as usual). The longer duration is what causes PTV clashes. Degreeing the cams is a must even with a mild cam.
Chris
Its now been confirmed by the dealer that there is PTV contact... does not happen at idol but at higher rpm it's still happening. Is there anyway these cams can be timed to work properly and if not would going with a milder cam such as the EX268H solve the PTV issue? I am hearing that Ford used three different suppliers of pistons and five different suppliers of rocker arms. I was told this combo makes it very hard to place any other cam in other than the Stock cams that came with the PI heads. Does anyone have any other suggestions on a fix. Thank you for the help!
Yes, after putting in the cams in i come to find out. With the 97 block/ flat head pistons/ PI heads and the 262AH cams it is a clearance issue.
There is no clearance issue with 262ah cams if they are correctly degreed, regardless if they are PI or NPI. Yes, the cams do have four degrees of advance ground in, but the tolerance on the keys is very sloppy. You don't degree these cams by the gear key or the cam key. You degree them using the Intake valve lobe centerline (ICL). The factory gears can be off by 5, even 6 degrees...so can the key on the cam. Add these tolerances up and you have a great recipe for disaster.
There is no difference in the potential for PTV on either PI or NPI pistons, either piston edge comes flush to the block. This is the location on the piston where PTV occurs on these engines.
The big difference on PI and NPI platforms concerning PTV is the intake valves. PI valves have a lip on the bottom which reduces your margin to PTV contact. This is nearly .060", which is a lot.
Your cams weren't properly degreed. Thats how this happened. You may have some bent valves or thrashed valve guides. You should have your passenger head disassembled and inspected. Take a look at your pistons while you are at it.
There is no difference in the potential for PTV on either PI or NPI pistons, either piston edge comes flush to the block. This is the location on the piston where PTV occurs on these engines.
The big difference on PI and NPI platforms concerning PTV is the intake valves. PI valves have a lip on the bottom which reduces your margin to PTV contact. This is nearly .060", which is a lot.
Your cams weren't properly degreed. Thats how this happened. You may have some bent valves or thrashed valve guides. You should have your passenger head disassembled and inspected. Take a look at your pistons while you are at it.
trinity_gt
10 Year Member
Similar threads
