275 GTB Valve Screw Excessive Wear

Jimmy Chen Shiba DDS · 11-19-2010, 05:58 PM

I have mentioned this problem under the "Ferrari Owners' 275 Section in the Running report of #08191. While I had the car in shop to repair hairline crack in the radiator, I was concerned about this "sound" of the engine and we decided to open the cover to see what was going on. Discovered were several excessviely worn out valve lash adjuster screws.

My question here is to ask for opinions as to what could have caused such wears in some of the screws ? The car underwent total overhaul several years back and is still under 3,000km since. Would appreciate any insights for my own learning curve. Thanx in advance.

Meanwhile, the shop is fabricating new screws for replacements. w/ smiles Jimmy

Boxer · 11-20-2010, 12:02 AM

Quote:

Originally Posted by Jimmy Chen Shiba DDS

My question here is to ask for opinions as to what could have caused such wears in some of the screws ? The car underwent total overhaul several years back and is still under 3,000km since.

Are you sure the screws were replaced when they did the overhaul?

Jimmy Chen Shiba DDS · 11-20-2010, 12:08 AM

Quote:

Originally Posted by Boxer

Are you sure the screws were replaced when they did the overhaul?

I am quite sure, Boxer. (Altho, this was done under the ownership of the previous owner). My understanding of complete overhaul is to check everything. They even replaced the no problem cams with a whole new set at the time (don't know why because the original ones look fine; I have them with me). w/ smiles Jimmy

Boxer · 11-20-2010, 02:53 AM

No idea why they would have worn so quickly then.

mk e · 11-20-2010, 03:43 AM

Quote:

Originally Posted by Boxer

No idea why they would have worn so quickly then.

The key might be in the statement:

"Meanwhile, the shop is fabricating new screws for replacements"

If the parts are not available form ferrari and were fabbed up then sending them out to have the alloy and hardness confirmed would be the only way to know if they ever met OEM spec of not. There are whole lot of alloys and heast treating processes out there, getting the dimensions correct is only 1 piece of the puzzle ......

12340 · 11-20-2010, 05:03 AM

Jimmy, the adjuster screws are made to wear. The valve stems are hardened so they don't mushroom, the adjusters are softer and made to be adjusted. Depending on the supplier will determine the quality of the parts. Contact Geoff Ohland at Partsource, 207-236-9791 he has the correct adjusters. Replace them all while you have the valve cover off. By the way Geoff used to work for Luigi Chinetti and is the best for vintage Ferrari parts.

Jimmy Chen Shiba DDS · 11-20-2010, 06:08 AM

Thanx for the comments, guys. Prior to my purchase last year, the previous owner had the car shipped to Italy from Japan (can you believe that ?!?!) for thorough overhaul, spending a bundle (got invoices). Don't bother asking how much, too much. Maybe that is when something went wrong. Since this resto, the km. meter was reset to zero and has clocked under 3,000km so far. As you can see, the wear of the screws crazy !

Anyway, I have contacted Mr. Roelof's shop who supply their own modified kit which should take care of this problem. I would try other suggestions too. In the meantime, new race quality screws are being ordered to be fabricated by a race shop. See how this works out. w/ smiles Jimmy

Jimmy Chen Shiba DDS · 11-20-2010, 06:10 AM

Quote:

Originally Posted by 12340

Jimmy, the adjuster screws are made to wear. The valve stems are hardened so they don't mushroom, the adjusters are softer and made to be adjusted. Depending on the supplier will determine the quality of the parts. Contact Geoff Ohland at Partsource, 207-236-9791 he has the correct adjusters. Replace them all while you have the valve cover off. By the way Geoff used to work for Luigi Chinetti and is the best for vintage Ferrari parts.

Thanx for your lead, 12340. I shall do so when I am back in LA next week. Thanx again. w/ smiles Jimmy

hhh · 11-22-2010, 11:20 AM

Piet Roelofs has the best modified parts for that. I have raced 275GTB's with them and they work well.
Before these were available I remember replacing some of them on a GTB/C 4 times in 3 days.............not funny.

Jimmy Chen Shiba DDS · 11-22-2010, 11:47 AM

Quote:

Originally Posted by hhh

Piet Roelofs has the best modified parts for that. I have raced 275GTB's with them and they work well.
Before these were available I remember replacing some of them on a GTB/C 4 times in 3 days.............not funny.

Thanx for your comment, hhh. Seems like Mr. Roelof's product is a must have. Did get a reply from his shop and the kit was quoted as 1575 Euro. w/ smiles Jimmy

ECSofVirginia · 11-22-2010, 02:18 PM

American cars have also suffered from ruined camshafts and solid lifters due to the protective additives being removed from modern oils.

You may want to pay close attention to what oil is being used in the car and whether or not additives are being used also to help avoid similar issues.

Jimmy Chen Shiba DDS · 11-22-2010, 11:26 PM

Quote:

Originally Posted by ECSofVirginia

American cars have also suffered from ruined camshafts and solid lifters due to the protective additives being removed from modern oils.

You may want to pay close attention to what oil is being used in the car and whether or not additives are being used also to help avoid similar issues.

Thanx, Josh. Would check this out too, as suggested. Thank You. w/ smiles Jimmy

Artvonne · 11-23-2010, 05:24 AM

A long time back I had some VW heads rebuilt. Short story was I had wear "opposite" of yours, the valve stems were going away within just a few 100 miles. The stems had been ground down past the hard end into the softer stem, and the adjusters hammered them flat in no time.

The valve stem end and the adjuster end are very, very hard metal, and should wear about equally against each other. In fact they really shouldn't show signs of wear before any other major parts have completely worn out several times.

So while oil, specifically the removal of zinc additives, have shown increased wear, I think you need to look more critically at the part itself as Mark suggested. If it were an oil issue that caused these parts to wear so rapidly, I think you would have some other issues.

I would locate a full set of OEM adjusters and replace all of them.

JazzyO · 11-25-2010, 09:33 AM

Quote:

Originally Posted by hhh

Piet Roelofs has the best modified parts for that. I have raced 275GTB's with them and they work well.
Before these were available I remember replacing some of them on a GTB/C 4 times in 3 days.............not funny.

Welcome here, hhh, nice to see such experienced owners chipping in.

Onno

212Export · 11-25-2010, 09:56 AM

Quote:

Originally Posted by hhh

Piet Roelofs has the best modified parts for that. I have raced 275GTB's with them and they work well.
Before these were available I remember replacing some of them on a GTB/C 4 times in 3 days.............not funny.

Was that your personal GTB/C ? Was it a first series (I guess) or a 2nd series GTB/C ?

11-19-2010, 05:58 PM	#1
Jimmy Chen Shiba DDS Owner Elite Member Join Date: Feb 2005 Location: Yokohama & Tokyo, Japan Ferrari Life Posts: 3,550 Name: Jimmy Chen Shiba	275 GTB Valve Screw Excessive Wear I have mentioned this problem under the "Ferrari Owners' 275 Section in the Running report of #08191. While I had the car in shop to repair hairline crack in the radiator, I was concerned about this "sound" of the engine and we decided to open the cover to see what was going on. Discovered were several excessviely worn out valve lash adjuster screws. My question here is to ask for opinions as to what could have caused such wears in some of the screws ? The car underwent total overhaul several years back and is still under 3,000km since. Would appreciate any insights for my own learning curve. Thanx in advance. Meanwhile, the shop is fabricating new screws for replacements. w/ smiles Jimmy Attached Images

11-20-2010, 02:53 AM	#4
Boxer Owner Elite Member Join Date: Apr 2004 Location: UK Ferrari Life Posts: 12,792	No idea why they would have worn so quickly then. Boxer Current: F40, F50, 612, 430 Scuderia Past: 360 Modena, 360 Challenge, 550, 575, 365BB, 512BB, 456 GT, F355 GTS, 365 GTB/4 Daytona, 308 GTB

11-20-2010, 05:03 AM	#6
12340 Master Mechanic Sponsor Join Date: Dec 2009 Ferrari Life Posts: 3	Jimmy, the adjuster screws are made to wear. The valve stems are hardened so they don't mushroom, the adjusters are softer and made to be adjusted. Depending on the supplier will determine the quality of the parts. Contact Geoff Ohland at Partsource, 207-236-9791 he has the correct adjusters. Replace them all while you have the valve cover off. By the way Geoff used to work for Luigi Chinetti and is the best for vintage Ferrari parts. www.rmccar.com

11-22-2010, 02:18 PM	#11
ECSofVirginia Master Mechanic Sponsor Join Date: Dec 2009 Location: Ashburn, VA Ferrari Life Posts: 477 Name: Josh Hill	American cars have also suffered from ruined camshafts and solid lifters due to the protective additives being removed from modern oils. You may want to pay close attention to what oil is being used in the car and whether or not additives are being used also to help avoid similar issues. Exotic Car Specialties www.ECSofVirginia.com 201 Davis Dr. Suite L Sterling, VA 20164 703.421.5356

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11-20-2010, 06:08 AM	#7
Jimmy Chen Shiba DDS Owner Elite Member Join Date: Feb 2005 Location: Yokohama & Tokyo, Japan Ferrari Life Posts: 3,550 Name: Jimmy Chen Shiba	Thanx for the comments, guys. Prior to my purchase last year, the previous owner had the car shipped to Italy from Japan (can you believe that ?!?!) for thorough overhaul, spending a bundle (got invoices). Don't bother asking how much, too much. Maybe that is when something went wrong. Since this resto, the km. meter was reset to zero and has clocked under 3,000km so far. As you can see, the wear of the screws crazy ! Anyway, I have contacted Mr. Roelof's shop who supply their own modified kit which should take care of this problem. I would try other suggestions too. In the meantime, new race quality screws are being ordered to be fabricated by a race shop. See how this works out. w/ smiles Jimmy

11-22-2010, 11:20 AM	#9
hhh Join Date: Dec 2009 Ferrari Life Posts: 2	Piet Roelofs has the best modified parts for that. I have raced 275GTB's with them and they work well. Before these were available I remember replacing some of them on a GTB/C 4 times in 3 days.............not funny.

11-23-2010, 05:24 AM	#13
Artvonne Owner Join Date: Jun 2010 Location: War Eagle Arkansas Ferrari Life Posts: 166 Name: Art	A long time back I had some VW heads rebuilt. Short story was I had wear "opposite" of yours, the valve stems were going away within just a few 100 miles. The stems had been ground down past the hard end into the softer stem, and the adjusters hammered them flat in no time. The valve stem end and the adjuster end are very, very hard metal, and should wear about equally against each other. In fact they really shouldn't show signs of wear before any other major parts have completely worn out several times. So while oil, specifically the removal of zinc additives, have shown increased wear, I think you need to look more critically at the part itself as Mark suggested. If it were an oil issue that caused these parts to wear so rapidly, I think you would have some other issues. I would locate a full set of OEM adjusters and replace all of them.