[DeTomaso] BBORR engine failure clues

asajay at asajay.com asajay at asajay.com
Thu Apr 30 12:25:40 EDT 2009


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
>>> >>>
>>> >> 2 SkyDrive(tm): Get 25 GB of free online storage.
>>> >>
>>> >> http://windowslive.com/online/skydrive?ocid=TXT_TAGLM_WL_skydrive_042009
>>> >>
>>> >>> _______________________________________________
>>> >>>
>>> >>> Detomaso Forum Managed by POCA
>>> >>>
>>> >>> Archive Search Engine Now Available at
>>> >>>
>>> >> http://www.realbig.com/detomaso/
>>> >>
>>> >>> DeTomaso mailing list
>>> >>> DeTomaso at list.realbig.com
>>> >>> http://list.realbig.com/mailman/listinfo/detomaso
>>> >>>
>>> >>
>>> >> _______________________________________________
>>> >>
>>> >> Detomaso Forum Managed by POCA
>>> >>
>>> >> Archive Search Engine Now Available at http://www.realbig.com/detomaso/
>>> >>
>>> >> DeTomaso mailing list
>>> >> DeTomaso at list.realbig.com
>>> >> http://list.realbig.com/mailman/listinfo/detomaso
>>> >>
>>> >>
>>> >>
>>> >>
>>> >>
>>> >> _______________________________________________
>>> >>
>>> >> Detomaso Forum Managed by POCA
>>> >>
>>> >> Archive Search Engine Now Available at http://www.realbig.com/detomaso/
>>> >>
>>> >> DeTomaso mailing list
>>> >> DeTomaso at list.realbig.com
>>> >> http://list.realbig.com/mailman/listinfo/detomaso
>>> >>
>>> >> ------------------------------------------------------------------------
>>> >>
>>> >>
>>> >> No virus found in this incoming message.
>>> >> Checked by AVG - www.avg.com
>>> >> Version: 8.0.238 / Virus Database: 270.12.8/2086 - Release Date:
>>> >> 04/29/09 06:37:00
>>> >>
>>> >>
>>> > _______________________________________________
>>> >
>>> > Detomaso Forum Managed by POCA
>>> >
>>> > Archive Search Engine Now Available at http://www.realbig.com/detomaso/
>>> >
>>> > DeTomaso mailing list
>>> > DeTomaso at list.realbig.com
>>> > http://list.realbig.com/mailman/listinfo/detomaso
>>> > _______________________________________________
>>> >
>>> > Detomaso Forum Managed by POCA
>>> >
>>> > Archive Search Engine Now Available at http://www.realbig.com/detomaso/
>>> >
>>> > DeTomaso mailing list
>>> > DeTomaso at list.realbig.com
>>> > http://list.realbig.com/mailman/listinfo/detomaso
>>> >
>>>
>>>
>>> _______________________________________________
>>>
>>> Detomaso Forum Managed by POCA
>>>
>>> Archive Search Engine Now Available at http://www.realbig.com/detomaso/
>>>
>>> DeTomaso mailing list
>>> DeTomaso at list.realbig.com
>>> http://list.realbig.com/mailman/listinfo/detomaso
>>
>>
>> _________________________________________________________________
>> Rediscover Hotmail®: Get quick friend updates right in your inbox.
>> http://windowslive.com/RediscoverHotmail?ocid=TXT_TAGLM_WL_HM_Rediscover_Updates2_042009
>> _______________________________________________
>>
>> Detomaso Forum Managed by POCA
>>
>> Archive Search Engine Now Available at http://www.realbig.com/detomaso/
>>
>> DeTomaso mailing list
>> DeTomaso at list.realbig.com
>> http://list.realbig.com/mailman/listinfo/detomaso
>>
>
>
> _______________________________________________
>
> Detomaso Forum Managed by POCA
>
> Archive Search Engine Now Available at http://www.realbig.com/detomaso/
>
> DeTomaso mailing list
> DeTomaso at list.realbig.com
> http://list.realbig.com/mailman/listinfo/detomaso
>





More information about the DeTomaso mailing list