last on blowback prob -:)
Still having problems of blowback, for which I have posted several hreads and had some good replies. As the problem has not been solved here is the full storie with all the details which hopefully bring possible solutions!
The car in question is an old militaryvehicle, from 1986, sold in 2003 to normal citizens. The car is a twin carb v8 3.5 litres. We are not sure wheter engine is pre 1986 or after, as it is a changeover year. It mihght not even be the orgiginal engine as there is a plague saying it was a 2.5 turbo diesel, but this could just been added after.
It has a new waterpump, and the last two parts of the exhaust are new, the coil is new, the distributor seems to be new also.
Two days before leaving the UK we had these two parts of the exhaust changed and used the parts of before the changeover in 1986 as was the advise of the mechanic. Maybe we should have used the parts for 1986 onwards as it was on our first trip leaving the UK that we started experiencing blowbacks. Does anyone have expereince with the resuls of wrong exhaust parts???
The problem is as folllows: there seem to be a small blowout on the exhaust and every so often a blowback (ignition fumes). It feels as if there is a misfiring or lack of fuel, as if someone slammed the brake. The is a sudden loss of power which then just as sudden, after 1-2secs comes back as normal.
Our right carburator (drivers site) damper pops op every couple of hours driving especially when puttin strains on engine such as in hilly areas or high speed motorways. The left damper (passenger side) also comes of every so often but not as much. Our distributor seems new, points are good, wires seem new and have just spaced all wires of away from engine. It is when carb spout pops out and up to the moment of us stopping and putting it back on that car seems to lose power and ability to drive uphill, also affecting excelleration. Machanics checked fuel flow by removing fuelfilter qnd flow was uninterupted. The blowbacks seem to come from where final exhaust section meets the manifold. Of the three bolts connecting these 1 appears loser than the other. A family friend suggested this as the problem yet machanic said a blowout of air is prefereable for engine than leaving hot air in the exhaust. Still we tried tightening it which resulted in the disapaering of the loss of power problem, yet more common blowouts with big bangs. However, not changing anything after the problem came back after a couple of hours. We did fill whole in exhaust but this was blownout soon after (so not such good home repair!!!) and we think this might just be a coincedence.
Problem ccurs mainly on motorway when driving around 65mph, but also around 35 and 15 and at other less specififc intervals.
We seem to have slight ooil leak as we seem to use 1l oil ever 500K. However no visibe leak but droplets have formed on bottom of oil sum. Water also has to be topped very often ( but then we are in Marocco).
The oil in the carbs had evaporated but now been refilled which made no difference (unlike 3rd mechanics assumption). Is it normal for the damper to come off and why is so? We have also just discovered that the two carb spouts are slightly different and have today changed them around to see what happens next.
We have absolutely racked our brains, mechanics either dont know or give incorrect solutions and then dont know. I realise I have bugged this forum already a few times so this will be my last Promise!!!!!!
Many thanks for reading this guys!!!!