Sign in

← All builds

brucejon2's Triumph TR3A restoration

brucejon2 · Triumph TR3A

Triumph TR3 and TR3A

TR3 Restoration Lessons Learned (TR3B project blog)

Read the full write-up at TR3 Restoration Lessons Learned (TR3B project blog) ↗

Photo: TR3 Restoration Lessons Learned (TR3B project blog)

Timing chain, front seal, motor mounts and fan balancing on a TR3A

Owner brucejon2 documents detailed engine-front work on a Triumph TR3A during a frame-up restoration: replacing a worn timing chain and tensioner, fitting a new front oil seal with a Speedi-Sleeve, installing uprated motor mounts, and hand-building a jig to statically balance the cooling fan assembly. The posts are written as practical lessons-learned notes with part numbers and sourcing tips for other TR3 owners.

Specs

As stated in the original write-up.

Timing chain
IWIS chain from Moss (Germany made)
Timing chain tensioner
Moss-sourced replacement, flat black finish, made in India
Front crank oil seal
Moss Part #520-000, made in Taiwan (CHO part 15639), fitted with a National Speedi-Sleeve #99174 over a worn hub groove
Motor mounts
Uprated mounts from The Roadster Factory
Timing chain cover
Repainted in black VHT engine paint, resurfaced for flatness, bondo used to replace sound deadening material

Parts used

Parts named as used in the original write-up, grouped the way the Parts page groups them. Where one of the shops we index lists the same thing for this car, it is shown underneath with a link to the shop.

Engine 5

Suspension & Steering 1

  • Uprated motor mountsThe Roadster Factory

    Replaced soft, worn original mounts; bolts shortened for easier fitting

Body & Trim 1

Tools & Workshop 1

Other 1

  • Wiring clip sleevesThe Roadster Factory

    Used for securing wiring clips; each sleeve cut into three clip lengths

Photos

15 pictures collected from the write-up, in the order they were posted, shown from TR3 Restoration Lessons Learned (TR3B project blog). A picture opens larger here, with the way through to the page it is on.

Replacing Front Oil Seal/Installing Speedi-Sleeve/Timing Chain/Motor Mounts on a Triumph TR3A 11this post at TR3 Restoration Lessons Learned (TR3B project blog) ↗

t4rmanualtimingchainPhoto: TR3 Restoration Lessons Learned (TR3B project blog)
Engine front with apron removed, work in progressPhoto: TR3 Restoration Lessons Learned (TR3B project blog)
Timing chain components during inspectionPhoto: TR3 Restoration Lessons Learned (TR3B project blog)
Timing chain cover being cleaned and preparedPhoto: TR3 Restoration Lessons Learned (TR3B project blog)
Motor mount area during removal or fittingPhoto: TR3 Restoration Lessons Learned (TR3B project blog)
Front of engine before parts installedPhoto: TR3 Restoration Lessons Learned (TR3B project blog)
Timing cover with new gasket being fittedPhoto: TR3 Restoration Lessons Learned (TR3B project blog)
Annotation 2020-06-13 191416Photo: TR3 Restoration Lessons Learned (TR3B project blog)
Motor mount bolts and hardwarePhoto: TR3 Restoration Lessons Learned (TR3B project blog)
Motor mount installed in placePhoto: TR3 Restoration Lessons Learned (TR3B project blog)
Finished timing chain cover installationPhoto: TR3 Restoration Lessons Learned (TR3B project blog)

Balancing, installing the Cooling Fan Assembly on a Triumph TR3A 3this post at TR3 Restoration Lessons Learned (TR3B project blog) ↗

Photo: TR3 Restoration Lessons Learned (TR3B project blog)
balancerPhoto: TR3 Restoration Lessons Learned (TR3B project blog)
Fan assembly balanced and ready to installPhoto: TR3 Restoration Lessons Learned (TR3B project blog)

Don’t overorder Roadster Factory Wiring Clip Sleeves for a Triumph TR3A 1this post at TR3 Restoration Lessons Learned (TR3B project blog) ↗

Photo: TR3 Restoration Lessons Learned (TR3B project blog)

How it was done

Timing chain and tensioner

With the front apron already off, the owner checked timing chain slack using a drill bit and found it exceeded the TR4 manual's wear spec, so he replaced it with an IWIS chain from Moss, chosen over cheaper options reported to stretch quickly. He also replaced the worn, grooved tensioner with a Moss-sourced unit rather than a pricier Racetorations upgrade.

Front oil seal and Speedi-Sleeve

Because the hub had a worn groove where the original seal rode, he installed a National Speedi-Sleeve along with a Moss front seal, sealed with Permatex non-hardening gasket dressing. He compared several seal part numbers and suppliers before settling on the Moss/CHO seal for its double sealing surface.

Timing cover and motor mounts

The timing chain cover was flattened, repainted, and refurbished with bondo replacing the original sound deadening material. He fitted a new gasket and washers, then installed uprated Roadster Factory motor mounts, noting the stock mount bolts were too long and shortening them for easier fitting.

Fan balancing

Unable to find a shop to balance the cooling fan assembly, the owner built his own static balancing jig from plywood and hacksaw blades. He balanced the fan extender hub and fan separately then together, adding washers as counterweights until it held position reliably before refitting it to the car.

Small parts ordering

He notes a minor lesson that Roadster Factory wiring clip sleeves yield three clips each, so he ended up with far more than needed after ordering based on total clip count.

A summary in our own words. The full account, with all its detail, is in the original write-up: read it at TR3 Restoration Lessons Learned (TR3B project blog) ↗

Worth knowing

  • Buy a quality timing chain (e.g. IWIS) rather than cheaper ones reported to stretch quickly
  • Check motor mount bolt length before fitting; stock-length bolts are longer than needed and hard to install
  • Order wiring clip sleeves by sleeve count, not clip count, since each sleeve yields three clips
  • Jacking the engine can pull the fuel line off near the shutoff tap, so take care when lifting for motor mount access
  • A worn hub groove under the front seal can be fixed with a Speedi-Sleeve instead of replacing the hub

FIND YOUR NEXT IDEA

Explore

VideosSearch videos and spoken topicsPartsFind parts from specialist storesBuildsLearn from other people’s projectsSocialsIdeas from the communityTechnical & communitiesGuides, advice and owner clubsGalleryBrowse photos and inspiration
brucejon2's Triumph TR3A restoration | Restomod Life