[DeTomaso] BBORR engine failure clues

Dave Londry davel at emspace.com
Thu Apr 30 14:23:50 EDT 2009 

Wait - dawgs don't get that.
(particularly if they're macaroon & marguerita immunized)

Mad Dog Antenucci wrote:
> Unsubscribe me....Could be swine flu
>
>  
> Mad Dawg Antenucci 
> Team Pantera Racing 
> The 1st & still the only vintage race team in open road racing 
> www.teampanteraracing.com
>
>
>
>
> ________________________________
> From: "asajay at asajay.com" <asajay at asajay.com>
> To: detomaso at realbig.com
> Sent: Thursday, April 30, 2009 9:25:40 AM
> Subject: Re: [DeTomaso] BBORR engine failure clues
>
> Whoops, forgot a couple things:
>
> - possible damage to pistons, from valve smacks... inspect, replace as  
> necessary
> - possible damage to piston rod, same excuse... same story.
>
> It kind of all depends on how hard a valve hit a piston, if it did.  
> Figure that load could transmit all the way to the crank, which means  
> you'd need to have the crank checked, replace bearings, etc.  I don't  
> with to sound like an alarmist, but now that you know the  
> possibilities, you'll be so much happier when you find most of these  
> items or okay.  :)
>
> Quoting asajay at asajay.com:
>
>   
>> Well... get the lifters out of their bores and inspect the cam.  Try
>> to move the cam with your fingers, or a screwdriver.  If it moves,
>> it's toast.  This is what most of us suspect at this point.
>>
>> Collateral damage?  Maybe, maybe not, or at least, nothing that should
>> require a whole new engine.  Here's my thoughts:
>>
>> - possible cam bearing damage... replace (could also be a cause of
>> failure if the bearings were not sized right to the cam)
>> - possible cam bits floating around in the system....  take it all
>> apart, clean, inspect, reassemble.
>> - possible bent valves on those two cylinders... remove heads, have serviced
>> - possible breakage of valve guides... ditto
>> - pushrods you already know about
>> - possible damage to rockers... inspect, replace as necessary
>> - cam plug at back of block
>> - possible damage on the cam retainer... inspect
>> - possible damage on the back side of the cam gear and chain... inspect
>> - possible damage to the distributor gear... inspect
>>
>> That's about all I can think of off the top of my head.
>>
>> If you need 12 other bent pushrods to match the new ones you recently
>> found, I can probably help you out there.  :)
>>
>> Asa Jay
>>
>> Quoting michael frazier <red3644 at hotmail.com>:
>>
>>     
>>> Ok, now back to my problem.  This engine does NOT have roller
>>> lifters.  Everytime I open a post hoping someone has
>>> great info about my failure or is willing to give me a new engine or
>>>  parts I see...JUST KIDDING, JUST KIDDING!
>>>
>>>
>>> I'm pretty sure it looks like a broken cam with 2 cylinder's lifters
>>>  down and oil in the bell housing area.  I don't have any
>>>
>>> experience with this.  Are there any common causes for this.  I
>>> assume it's a result of torsional loads, but?  What kind of
>>>
>>> collateral damage is likely?  I can imagine some block damage, bent
>>> valves etc.  Thanks for any info...and that was good info on roller
>>> lifters too.  :)
>>>
>>> Michael
>>>
>>>       
>>>> Date: Thu, 30 Apr 2009 07:58:53 -0700
>>>> From: asajay at asajay.com
>>>> To: detomaso at realbig.com
>>>> Subject: Re: [DeTomaso] BBORR engine failure clues
>>>>
>>>> Very good point Gray, thank you for clarifying.
>>>>
>>>> Asa Jay
>>>>
>>>> Quoting Gray Gregory <rgg at gregorycook.com>:
>>>>
>>>>         
>>>>> Asa,
>>>>>
>>>>> You can add me to that list too. I agree with John that solid roller
>>>>> lifters are a problem waiting to happen and are not worth the extra
>>>>> hp for a street driven car, of course that's just my opinion!
>>>>>
>>>>> It's important that we separate solid roller lifters and hydraulic!
>>>>> The modern engines you talk about all have hydro roller lifters and
>>>>> the shock absorption effect the hydro lifters give you eliminates
>>>>> the problem of the needle bearings failing from the shock as the
>>>>> lash is taken up.
>>>>>
>>>>> Gray
>>>>>
>>>>> -----Original Message-----
>>>>> From: detomaso-bounces at realbig.com
>>>>> [mailto:detomaso-bounces at realbig.com] On Behalf Of Asa Jay Laughton
>>>>> Sent: Wednesday, April 29, 2009 11:43 PM
>>>>> To: detomaso at realbig.com
>>>>> Subject: Re: [DeTomaso] BBORR engine failure clues
>>>>>
>>>>> I don't see them as a "frequent" source of engine failure. I've seen
>>>>> more engine failures talked about due to broken valves, overbores that
>>>>> "windowed" a cylinder wall, broken cams, worn mechanical lifters,
>>>>> sheared distributor pins, and the list goes on. I've only heard of one
>>>>> failure due to a roller lifter going out, and that was today from John
>>>>> Taphorn. So I'm not really seeing any data that roller lifters are a
>>>>> frequent source of failure.
>>>>>
>>>>> For what it's worth.... most modern engines only use roller lifters now,
>>>>> which is why most cam grinders now have lower profile grinds for use
>>>>> with roller lifters. It used to be if you wanted to use roller lifters,
>>>>> your cam selection was very limited, usually to strip and track only
>>>>> grinds. Nowdays you can get a good street grind for everyday driving.
>>>>>
>>>>> Is it worth it? Heck yea... reduced friction, reduced load, both of
>>>>> which lead to better gains in HP. Modern components last a lot longer,
>>>>> etc. What's not to like about them?
>>>>>
>>>>> Asa Jay
>>>>>
>>>>> Asa Jay Laughton, MSgt, USAFR, Retired
>>>>>
>>>>> & Shelley Marie
>>>>> Spokane, WA
>>>>>
>>>>> 1971 Mach I Mustang [ASA JAY]
>>>>> 1973 Pantera L 5533 [ASASCAT]
>>>>>
>>>>> ******************************
>>>>> http://www.asajay.com
>>>>> http://www.teampanteraracing.com
>>>>>
>>>>>
>>>>>
>>>>>
>>>>> pantdino at aol.com wrote:
>>>>>           
>>>>>> To admit my ignorance:
>>>>>> Seems like these roller cam followers are a frequent source of engine
>>>>>> failure.
>>>>>> Is it really worth it? Do you really gain that many HP?
>>>>>>
>>>>>> Jim
>>>>>>
>>>>>>
>>>>>>
>>>>>> -----Original Message-----
>>>>>> From: John Taphorn <jtaphorn at kingwoodcable.com>
>>>>>> To: michael frazier <red3644 at hotmail.com>; pantera list
>>>>>> <detomaso at realbig.com>
>>>>>> Sent: Wed, 29 Apr 2009 8:16 pm
>>>>>> Subject: Re: [DeTomaso] BBORR engine failure clues
>>>>>>
>>>>>>
>>>>>>
>>>>>>
>>>>>>
>>>>>>
>>>>>>
>>>>>>
>>>>>>
>>>>>>
>>>>>> Michael
>>>>>>
>>>>>> I believe that you stated you were running a solid roller lifter cam.
>>>>>> The
>>>>>> excess lash occurs as the needle bearings in the roller's wheels turn
>>>>>> to
>>>>>> dust. The base of the roller then rides on the cam lobe and the wear
>>>>>> rapidly against one another.
>>>>>>
>>>>>> Welcome to solid roller hell from one who has made the journey.
>>>>>>
>>>>>> JT
>>>>>> ----- Original Message -----
>>>>>> From: "michael frazier" <red3644 at hotmail.com>
>>>>>> To: "pantera list" <detomaso at realbig.com>
>>>>>> Sent: Wednesday, April 29, 2009 9:36 PM
>>>>>> Subject: [DeTomaso] BBORR engine failure clues
>>>>>>
>>>>>>
>>>>>>
>>>>>>             
>>>>>>> I had a chance to pull the distributor, intake and valve covers
>>>>>>>
>>>>>>>               
>>>>>> tonight.
>>>>>>
>>>>>>             
>>>>>>> The dist. gear is pinned tight where it should be. The rockers
>>>>>>>
>>>>>>> (intake and exhaust) for the back two cylinders, 4 & 8, are loose and
>>>>>>> almost off the springs. Lifters are down. That's as far as I've
>>>>>>> got...any new thoughts? I'll keep you posted.
>>>>>>>
>>>>>>> Michael
>>>>>>>
>>>>>>> _________________________________________________________________
>>>>>>> Windows Live=E
>>>>>>>
>>>>>>>

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