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Timing set replacement gone wrong by Will
Started on: 01-13-2018 09:49 PM
Replies: 11 (541 views)
Last post by: fierogt28 on 12-03-2018 08:45 PM
Will
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Report this Post01-13-2018 09:49 PM Click Here to See the Profile for WillClick Here to Email WillSend a Private Message to WillEdit/Delete MessageReply w/QuoteDirect Link to This Post

Car: 1988 Formula 5 speed; ~198k miles

Historical maintenance in this area: water pump replaced in 2006; have mileage recorded but not handy.

Failure event: Driving at 65 mph. Tach dropped instantly to zero and CEL illuminated. Engine braking dramatically reduced. After stop and attempting restart, cranks very fast and "doesn't sound right".

Diagnosis:
No spark
Some symptoms of ignition module failure, so swap modules.
Still no spark
Probe coil and module power to verify fusible link H is intact. It is.
Crank with distributor cap removed.
Rotor does not rotate.
At 200k miles a timing chain failure is much more likely than a sheared camshaft, so get started on that.

The timing cover is cast aluminum and two sided. The inner side is exposed to the timing drive while the outer side provides the back of the water pump. The water pump bolts directly to the timing cover, but some of its bolts go through the timing cover and directly into the block. However, the bolt holes have corroded on the inside, making the bolts very difficult to remove, even though they are not screwed into the aluminum.

There are four usages of bolts:
10mm x 75 mm (4x): These straddle the water inlets to the block. From the factory, two of these have T50 heads and two have 15mm hex heads with ~15 mm long studs
8mm x 70 mm (4x): These go through the water pump and timing cover, threading into the block. These have T40 heads.
8mm x 35 mm (3x): These go through the timing cover only, threading into the block. These have T40 heads.
6mm x 25 mm (4x): These go through the water pump only, threading into the timing cover. These have T30 heads.

Stuff that went wrong:

Broke a T50 bit
Broke a T40 bit
Rounded out a T50 bolt
Rounded out a T40 bolt
Wrung off a 10mm stud headed bolt
All other bolts through the water pump corroded, nearly seized and extremely difficult to remove.

I had a friend weld an expendable socket to the 10mm/T50 bolt and successfully unscrewed it, although I can't remove it until the timing cover and water pump assembly is out of the car.
We will deal with the rounded out 8mm/T40 bolt the same way tomorrow.
Getting the water pump and timing cover off the broken bolt is not expected to be what most people call fun.

Needless to say, there will be zero torx heads among the bolts that go back onto the car.

Pics tomorrow.

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Gall757
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Report this Post01-14-2018 01:32 PM Click Here to See the Profile for Gall757Send a Private Message to Gall757Edit/Delete MessageReply w/QuoteDirect Link to This Post

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Will
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Report this Post01-14-2018 02:54 PM Click Here to See the Profile for WillClick Here to Email WillSend a Private Message to WillEdit/Delete MessageReply w/QuoteDirect Link to This Post

Welded a socket to the T40 bolt today and got it out.
Water pump came off and the captive welded T50 bolt came with.

The timing cover is seized HARD to the formerly stud headed broken 10mm bolt. We're figuring that out.

This may end up with an engine swap.

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Kevin87FieroGT
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Report this Post01-14-2018 07:29 PM Click Here to See the Profile for Kevin87FieroGTSend a Private Message to Kevin87FieroGTEdit/Delete MessageReply w/QuoteDirect Link to This Post

Have you tried heat. Mapp gas is your friend.

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David Hambleton
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Report this Post01-14-2018 07:49 PM Click Here to See the Profile for David HambletonClick Here to Email David HambletonSend a Private Message to David HambletonEdit/Delete MessageReply w/QuoteDirect Link to This Post

I've plug welded nuts to the remains of bolts in lieu of a socket. Don't know if that's possible here...

[This message has been edited by David Hambleton (edited 01-14-2018).]

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Will
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Report this Post01-14-2018 08:19 PM Click Here to See the Profile for WillClick Here to Email WillSend a Private Message to WillEdit/Delete MessageReply w/QuoteDirect Link to This Post

Given how hard it's seized and how close EVERYTHING, including fuel lines, is... I'm going to rent a car this week and figure it out next weekend. I'm pretty sure the 2.8 will have to come out, and if it comes out, it's not going back in.
It's not in my garage or I wouldn't be as annoyed about it as I am.

At any rate, it's time to stop relying on 1980's technology.

[This message has been edited by Will (edited 01-14-2018).]

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Will
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Report this Post01-27-2018 01:32 PM Click Here to See the Profile for WillClick Here to Email WillSend a Private Message to WillEdit/Delete MessageReply w/QuoteDirect Link to This Post

Pictures still to follow...
I have the front cover off... it had seized to one of the 10mm water pump bolts. Feh.

The chain guide had broken off and gone between the chain and the crank sprocket, causing the chain to break. The chain itself and the sprockets are in fine shape but that F@$%ing guide is worn-ass out.

The oil pressure tube between the filter boss and the oil pressure sender is seized to the flare nut. Are those available in the aftermarket? I have one I can likely steal from The Mule's original engine, but if I can get one new I'd prefer that.

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fierogt28
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Report this Post02-18-2018 02:08 AM Click Here to See the Profile for fierogt28Send a Private Message to fierogt28Edit/Delete MessageReply w/QuoteDirect Link to This Post

Will, the chain guide is available from TFS, but the oil pressure sending tube may be a challenge.

TFS used to have them as new reproductions. The reason I'm interested is I wanted a new spare myself.

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fierogt28

88 GT, Loaded, 5-speed.
88 GT, 5-speed. Beechwood interior, All original.

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Will
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Report this Post02-19-2018 04:34 PM Click Here to See the Profile for WillClick Here to Email WillSend a Private Message to WillEdit/Delete MessageReply w/QuoteDirect Link to This Post

I was able to rescue the oil pressure tube with some heat on the nut. The car's back together and running now. I've uploaded the photos... I've just been busy and procrastinating about writing the whole ordeal up.

The piece of the guide that broke off went between the timing chain and the crank sprocket, breaking the chain. Replacing only the guide was not an option, and a new timing set comes with a new guide.

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fierogt28
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Report this Post02-28-2018 01:11 AM Click Here to See the Profile for fierogt28Send a Private Message to fierogt28Edit/Delete MessageReply w/QuoteDirect Link to This Post

Bump for pics...

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Blacktree
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Report this Post02-28-2018 10:04 AM Click Here to See the Profile for BlacktreeClick Here to visit Blacktree's HomePageClick Here to Email BlacktreeSend a Private Message to BlacktreeEdit/Delete MessageReply w/QuoteDirect Link to This Post

Multiple cycles of heating and dousing with penetrating oil will usually (eventually) get the job done. Also, a pro tip: after you get the oil pressure tube loose, pull back the fitting and clean off the tube with some fine sandpaper. Then put a light coating of anti-seize compound on the tube before you slide the fitting back in place. That should make it easier next time around.

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fierogt28
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Report this Post12-03-2018 08:45 PM Click Here to See the Profile for fierogt28Send a Private Message to fierogt28Edit/Delete MessageReply w/QuoteDirect Link to This Post

Will, did you have interest in updating this thread?

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fierogt28

88 GT, Loaded, 5-speed.
88 GT, 5-speed. Beechwood interior, All original.

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