Trouble starting after HG change

For all Carb and Injection engines, standard or modified plus non-standard engine transplants. Heads; Blocks; Cooling (including heater issues related to the cooling system); Mounts etc
Forum rules
Hints, tips and guides for repair and modification - the FAQ section on the main website is worth checking first for information relating to common faults and technical help. Useful posts and guides will be added to the FAQ http://www.sciroccoregister.co.uk/scirocco-faq
Post Reply
NebToast
Posts: 57
Joined: Sun Aug 26, 2018 4:27 pm
fill in the right answer: 15

Trouble starting after HG change

Post by NebToast »

I've just done the head gasket, replaced full Colling system and had the head skimmed and reconditioned on my 1992 EX 1.8 carby. Lined it all back up according to the right marks and my extra safety tip ex marks and double checked by turning over by hand so that's not the issue. But I started it today (turned it over without coil connected to build oil pressure first) and it spluttered a bit then fired but at very low rpm, 100 or so. It dies if you touch the throttle.

Anyway any suggestions for why it's not running at all right (I'd assumed timing would need adjustment a bit given the skim but not this much), maybe I've got the dizzy cap on the wrong way around? (I marked the plug numberings and left them in the cap so it can only be 180 out). Fuel is getting to the Weber and I've checked for spark in the leads using my strobe gun. Bit of a conundrum


User avatar
essextom
Posts: 991
Joined: Sat Feb 18, 2012 6:27 pm
fill in the right answer: 10
Location: Chelmsford

Re: Trouble starting after HG change

Post by essextom »

double check timing marks to start with.


NebToast
Posts: 57
Joined: Sun Aug 26, 2018 4:27 pm
fill in the right answer: 15

Re: Trouble starting after HG change

Post by NebToast »

I double checked timing marks on sprockets, dizzy, flywheel and with a screwdriver down the hole. The dizzy wasn't quite marked up so after tipexing the old position just in case I advanced it to line the rotor with the tdc mark. This made things run! I timed it up to the 6dbtc mark with my gun and checked by driving around the car park. Revved smoothly.

The motor sounds a bit tappety, it taps with engine speed. Is this because the heads been off and the tappets are dry, running for a while fix? Or is this what "pinking" is, the noise didn't change at all when adjusting timing so I am doubtful of that. Is it a fairly common noise or something I should be worried about? I've checked without the alternator so it's not that rubbing on the belt cover. It could be an exhaust leak I suppose.

Here's a video:
https://photos.google.com/share/AF1QipO ... lSMmZIdER3


NebToast
Posts: 57
Joined: Sun Aug 26, 2018 4:27 pm
fill in the right answer: 15

Re: Trouble starting after HG change

Post by NebToast »

Just took it for a bit of a drive and the noise has gone, it must have been the tappets refilling


mark1gls
Posts: 3954
Joined: Thu Apr 02, 2009 9:28 pm
fill in the right answer: 10
Location: Somerset

Re: Trouble starting after HG change

Post by mark1gls »

It can take a rev of the engine to get the oil pressure up and rid of tappet noise, glad it's now gone.
Dont forget to check the belts tension in 100 ish miles and might be worth changing the oil at 5,000 miles if you do 10,000 miles + a year.


Mk1 78 Scirocco GLS 1.6 FR, weekend toy.
Mk1 88 Golf GTi cabriolet 1.8 DX. Daily drive.
Membership No. 323
NebToast
Posts: 57
Joined: Sun Aug 26, 2018 4:27 pm
fill in the right answer: 15

Re: Trouble starting after HG change

Post by NebToast »

Took it for a good drive today, 40 minutes or so. The tappet noise was there when I stopped and opened the bonnet afterwards. Returned when the engine was hot. Any ideas why?

Also I fitted a larger rad and new temp sender and the dial reads a bit higher than it used to at normal running temps. Is this normal, some disparity between senders? The top hoses get to about 85 before the fan kicks in according to my temperature gun, which sounds fine. I'm using a larger slimline fan for cooling without any cowling but it seems to do the job. Any advice appreciated


mark1gls
Posts: 3954
Joined: Thu Apr 02, 2009 9:28 pm
fill in the right answer: 10
Location: Somerset

Re: Trouble starting after HG change

Post by mark1gls »

What oil are you using?


Mk1 78 Scirocco GLS 1.6 FR, weekend toy.
Mk1 88 Golf GTi cabriolet 1.8 DX. Daily drive.
Membership No. 323
NebToast
Posts: 57
Joined: Sun Aug 26, 2018 4:27 pm
fill in the right answer: 15

Re: Trouble starting after HG change

Post by NebToast »

Gave it an oil change with 10w40 before a long trip on Friday. It hasn't missed a beat performance wise but the noise is still sort of there.


mark1gls
Posts: 3954
Joined: Thu Apr 02, 2009 9:28 pm
fill in the right answer: 10
Location: Somerset

Re: Trouble starting after HG change

Post by mark1gls »

So it’s the right oil...
Can you post up a video of the noise if possible, just so we can check what you are hearing is the tappets and noting else...

It is possible to dismantle the tappets and clean them out or you can buy replacement, timing belt and cam shaft need to come off to replace/clean them.


Mk1 78 Scirocco GLS 1.6 FR, weekend toy.
Mk1 88 Golf GTi cabriolet 1.8 DX. Daily drive.
Membership No. 323
NebToast
Posts: 57
Joined: Sun Aug 26, 2018 4:27 pm
fill in the right answer: 15

Re: Trouble starting after HG change

Post by NebToast »

Noise can be heard in the top video


mark1gls
Posts: 3954
Joined: Thu Apr 02, 2009 9:28 pm
fill in the right answer: 10
Location: Somerset

Re: Trouble starting after HG change

Post by mark1gls »

You could try and clean out all the old oil out of the tappets and fill them with fresh oil, straight forward job but allow time for soaking the tappets in new oil, they are a simple ball bearing on a spring to allow oil to flow in and out and can get blocked up.

Guides on the web and videos on YouTube..

https://forums.vwvortex.com/showthread. ... ur-tappets


Mk1 78 Scirocco GLS 1.6 FR, weekend toy.
Mk1 88 Golf GTi cabriolet 1.8 DX. Daily drive.
Membership No. 323
Thomasd56
Posts: 1
Joined: Tue Jan 21, 2020 1:43 pm
fill in the right answer: 15

Re: Trouble starting after HG change

Post by Thomasd56 »

NebToast wrote: Mon Apr 15, 2019 6:21 pm I double checked timing marks on sprockets, dizzy, flywheel and with a screwdriver down the hole. The dizzy wasn't quite marked up so after tipexing the old position just in case I advanced it to line the rotor with the tdc mark. This made things run! I timed it up to the 6dbtc mark with my gun and checked by driving around the car park. Revved smoothly.

The motor sounds a bit tappety, it taps with engine speed. Is this because the heads been off and the tappets are dry, running for a while fix? Or is this what "pinking" is, the noise didn't change at all when adjusting timing so I am doubtful of that rachat de credit banque. Is it a fairly common noise or something I should be worried about? I've checked without the alternator so it's not that rubbing on the belt cover. It could be an exhaust leak I suppose.

Here's a video:
https://photos.google.com/share/AF1QipO ... lSMmZIdER3
Maybe we should grease a little to see if this is really the case.


Post Reply